Article of footwear with soil-shedding performance

ABSTRACT

The disclosure relates to articles of footwear ( 100 ) and components thereof, including outsoles ( 112 ), which can be used in conditions normally conducive to the accumulation of soil on the outsoles ( 112 ). In particular, the disclosure relates to articles of footwear ( 100 ) and components thereof including an outsole ( 112 ) with a material ( 116 ) including a polymeric network formed of a plurality of polymer chains, where the material ( 116 ) defines external ground-facing surface or side of the outsole ( 112 ). The outsoles ( 112 ) can prevent or reduce the accumulation of soil on the footwear ( 100 ) during wear on unpaved surfaces such as sporting fields.

FIELD

The present disclosure relates to articles of footwear. In particular,the present disclosure is directed to articles of footwear andcomponents thereof, including outsoles, which are used in conditionsconducive the accumulation of soil on the outsoles.

BACKGROUND

Articles of footwear of various types are frequently used for a varietyof activities including outdoor activities, military use, andcompetitive sports. The outsoles of these types of footwear often aredesigned to provide traction on soft and slippery surfaces, such asunpaved surfaces including grass and dirt. For example, exaggeratedtread patterns, lugs, cleats or spikes (both integral and removable),and rubber formulations which provide improved traction under wetconditions, have been used to improve the level of traction provided bythe outsoles.

While these conventional means generally help give footwear improvedtraction, the outsoles often accumulate soil (e.g., inorganic materialssuch as mud, dirt, sand and gravel, organic material such as grass,turf, and other vegetation, and combinations of inorganic and organicmaterials) when the footwear is used on unpaved surfaces. In someinstances, the soil can accumulate in the tread pattern (when a treadpattern is present), around and between lugs (when lugs are present), oron shafts of the cleats, in the spaces surrounding the cleats, and inthe interstitial regions between the cleats (when cleats are present).The accumulations of soil can weigh down the footwear and interfere withthe traction between the outsole and the ground.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the disclosure, reference should bemade to the following detailed description and accompanying drawingswherein:

FIG. 1 is a bottom isometric view of an article of footwear in an aspectof the present disclosure having an outsole including a material (e.g.,in the form of a film) in accordance with the present disclosure;

FIG. 2 is a bottom view of the outsole of the article of footwear shownin FIG. 1, where an upper of the footwear is omitted;

FIG. 3 is a lateral side view of the outsole shown in FIG. 2;

FIG. 4 is a medial side view of the outsole shown in FIG. 2;

FIG. 5 is an expanded sectional view of a portion of the outsole,illustrating a material in accordance with the present disclosure in adry state secured to a backing plate adjacent to a traction element(e.g., a cleat).

FIG. 5A is an expanded sectional view of the portion of the outsoleshown in FIG. 5, where the material is partially saturated and swollen.

FIG. 5B is an expanded sectional view of the portion of the outsoleshown in FIG. 5, where the material is fully saturated and swollen.

FIGS. 6-9 are expanded sectional views of the portion of the outsoleshown in FIG. 5, illustrating the soil-shedding performance of theoutsole during a foot strike motion on an unpaved surface.

FIG. 10 is a side cross-sectional view of an outsole in an aspectaccording to the disclosure including a soil-shedding material and soilbeing shed therefrom, during impact with a ground surface;

FIG. 11 is a bottom view of an article of footwear in another aspect ofthe present disclosure having an outsole including a material inaccordance with the present disclosure, the material having discrete andseparate sub-segments;

FIG. 12 is an expanded sectional view of a portion of an outsole inanother aspect of the present disclosure, which includes a material inaccordance with the present disclosure, the material being present in arecessed pocket of an outsole backing plate;

FIG. 13 is an expanded sectional view of a portion of an outsole inanother aspect of the present disclosure, which includes an outsolebacking plate having one or more indentations, and a material inaccordance with the present disclosure, the material being present inand over the indentations;

FIG. 14 is an expanded sectional view of a portion of an outsole inanother aspect of the present disclosure, which includes an outsolebacking plate having one or more indentations having locking members,and a material in accordance with the present disclosure, the materialbeing present in and over the indentations;

FIG. 15 is a bottom view of an article of footwear in another aspect ofthe present disclosure, which illustrates an example golf shoeapplication;

FIG. 16 is a bottom perspective view of an article of footwear inanother aspect of the present disclosure, which illustrates an examplebaseball shoe application;

FIG. 17 is a bottom perspective view of an article of footwear inanother aspect of the present disclosure, which illustrates an exampleAmerican football shoe application;

FIG. 18 is a bottom perspective view of an article of footwear inanother aspect of the present disclosure, which illustrates an examplehiking shoe application;

FIG. 19 is a photograph of an example a material of the presentdisclosure; and

FIGS. 20A-H include photographs of articles of footwear with and withouta material according to the disclosure after being worn and used duringwet and muddy game conditions.

The articles of footwear shown in the figures are illustrated for usewith a user's right foot. However, it is understood that the followingdiscussion applies correspondingly to left-footed articles of footwearas well.

DESCRIPTION

It has now been discovered that particular materials comprising apolymeric network formed of a plurality of polymer chains when disposedon a ground-facing surface of an outsole of an article of footwear canbe effective at preventing or reducing the accumulation of soil on theoutsole during wear on unpaved surfaces. Additionally, it has been foundthat the selection of certain materials, in terms of their physicalcharacteristics as measured using the test methods described herein, isuseful to achieve specific performance benefits for the outsoles and/oran article of footwear as disclosed herein.

Accordingly, the present disclosure describes outsoles formed of thesematerials which include a polymeric network formed of a plurality ofpolymer chains, articles of footwear made using these outsoles, use ofthese materials in outsoles, as well as methods of manufacturing andusing the outsoles and articles of footwear. The material which includesthe polymeric network formed of a plurality of polymer chains defines atleast a portion of a surface or side of the outsoles. In other words,the material is present at or forms the whole of or part of an outersurface of the outsole. When the outsole is included in an article offootwear, the material defines at least a portion of an exterior surfaceof the article or a side of the article which is ground-facing.

As can be appreciated, preventing or reducing soil accumulation on thebottom of footwear can provide many benefits. Preventing or reducingsoil accumulation on outsoles during wear on unpaved surfaces also cansignificantly affect the weight of accumulated soil adhered to theoutsole during wear, reducing fatigue to the wearer caused by theadhered soil. Preventing or reducing soil accumulation on the outsolecan help preserve traction during wear. For example, preventing orreducing soil accumulation on the outsole can improve or preserve theperformance of traction elements present on the outsole during wear onunpaved surfaces. When worn while playing sports, preventing or reducingsoil accumulation on outsoles can improve or preserve the ability of thewearer to manipulate sporting equipment such as a ball with the outsoleof the article of footwear.

In a first aspect, the present disclosure is directed to an outsole foran article of footwear. The outsole can be an outsole comprising a firstside; and an opposing second side; wherein the first side comprises amaterial, and the material compositionally comprises a polymeric networkformed of a plurality of polymer chains. The outsole can be an outsolecomprising a first surface configured to be ground-facing; and a secondsurface of the outsole opposing the first surface. At least a portion ofthe first surface of the outsole comprises a material defining at leasta portion of the first surface, and the material compositionallycomprises a polymeric network formed of a plurality of polymer chains.The plurality of polymer chains can comprise one or more hard segments;and one or more soft segments covalently bonded to the hard segments,wherein the one or more soft segments are present in the copolymerchains at a ratio ranging from 20:1 to 110:1 by weight relative to theone or more hard segments. In other words, a material having a polymericnetwork formed of a plurality of polymer chains is present at anddefines at least a portion of the first surface or first side of theoutsole.

The outsole can be configured to be secured to an upper of an article offootwear. In particular, the second surface of the outsole can beconfigured to be secured to an upper of an article of footwear. Theoutsole can be an outsole which prevents or reduces soil accumulationsuch that the outsole retains at least 10% less soil by weight ascompared to a second outsole which is identical to the outsole exceptthat the second outsole is substantially free of the material comprisinga polymeric network formed of a plurality of polymer chains.

In accordance with the present disclosure, the polymericnetwork-containing material of the outsole (and thus the portion of theoutsole which includes the material) can be a material which can becharacterized based on its chemical structure. As previously described,the material can compositionally comprise a polymeric network formed ofa plurality of polymer chains that comprise one or more hard segments;and one or more soft segments covalently bonded to the hard segments,wherein the one or more soft segments are present in the copolymerchains at a ratio ranging from 20:1 to 110:1 by weight relative to theone or more hard segments. The one or more hard segments are physicallycrosslinked to other hard segments of the copolymer chains.

The hard segments of the copolymer chains can comprise carbamatelinkages, amide linkages, or combinations thereof. The portions of thehydrophilic soft segments can be covalently bonded to the hard segmentthrough carbamate linkages. The hydrophilic soft segments of thecopolymer chains can comprise polyether segments, polyester segments,polycarbonate segments, or combinations thereof. At least a portion ofthe one or more hydrophilic soft segments can constitute backbonesegments of the copolymer chain. At least a portion of the hydrophilicsoft segments can comprise one or more pendant polyether groups. The oneor more hydrophilic soft segments can be present in the copolymer chainsat a ratio ranging from 40:1 to 110:1 by weight relative to the one ormore hard segments. The polymeric network can be a crosslinked polymericnetwork. The polymeric network can be a network formed of copolymerchains. The polymer chains of the polymeric network comprisepolyurethane chain segments, polyamide chain segments, or both.

It has also been found that particular hydrophilic polymers, includingcopolymers, polymeric blends, and polymeric networks, can be effectiveat reducing or preventing the accumulation of soil on the outsole duringwear on unpaved surfaces when the hydrophilic polymer is disposed on atleast a portion of the ground facing surface of an outsole. Thehydrophilic polymers can have properties as determined using the testmethods described herein, and are useful in achieving the specificperformance benefits for the outsoles and/or an article of footwear asdisclosed herein. The hydrophilic polymers, including the polymer chainsof the polymeric network of the material described herein, as well asthe polymeric networks themselves, can be described based on theirsegmental polarity, as determined using the Polymer Segmental PolarityDetermination described below. In some examples, at least 50% on a molarvolume basis of the polymer chains of the polymeric network can have asegmental polarity of less than 1.0 as determined using the PolymerSegmental Polarity Determination. The polymeric network of the materialcan consist essentially of polymer chains have a segmental polarity ofless than 1.0 as determined using the Polymer Segmental PolarityDetermination. Alternatively or in addition, the overall segmentalpolarity of the polymeric network can be less than 1.0 as determinedusing the Polymer Segmental Polarity Determination. At least 50% on amolar volume basis of the polymer chains of the polymeric network canhave a segmental polarity of less than 0 as determined using the PolymerSegmental Polarity Determination. The polymeric network of the materialcan consist essentially of polymer chains have a segmental polarity ofless than 0 as determined using the Polymer Segmental PolarityDetermination. The overall segmental polarity of the polymeric networkcan be less than 0 as determined using the Polymer Segmental PolarityDetermination.

Additionally, the polymeric network-containing material of the presentdisclosure can be characterized based on its physical properties, aswill be described below. For example, the material can be describedbased on its water uptake capacity, its water uptake rate, its swellingcapacity, its glass transition temperature, its storage modulus, thecontact angle of its surface, and the coefficient of friction of itssurface, as described below.

The outsoles of the present disclosure can also or alternatively becharacterized based on their structure such as, for example, thethickness of the material on the ground-facing outsole surface, how thematerial is arranged on the outsole, whether or not traction elementsare present, whether or not the material is affixed to an outsolebacking plate, and the like. The outsole can be an outsole having thematerial present on at least 80% of the ground-facing surface of theoutsole. The polymeric network-containing material of the outsole canhave a dry-state thickness ranging from 0.1 millimeters to 5millimeters, or from 0.1 millimeters to 1.0 millimeter. The outsole cancomprises one or more traction elements present on the first surface ofthe outsole. The outsole can further comprise an outsole backing member.The outsole backing member can form at least a portion of or be securedto the outsole, wherein the material is secured to the outsole backingmember such that the material defines the at least a portion of thefirst surface of the outsole.

In a second aspect, the present disclosure is directed to an article offootwear comprising an outsole as disclosed herein. The article offootwear can be an article comprising an outsole and an upper, whereinthe outsole has a first, ground-facing surface and a second surfaceopposing the first surface, wherein the upper is secured to the secondsurface of the outsole, wherein a material comprising a polymericnetwork formed of a plurality of polymer chains defines at least aportion of the ground-facing first surface of the outsole. The materialcan be a material as described above, e.g. with respect to the firstaspect of the disclosure. The article of footwear can be an articlewhich prevents or reduces soil accumulation such that the articleretains at least 10% less soil by weight as compared to a second articleof footwear which is identical to the article except that an outsole ofthe second article is substantially free of the material comprising apolymeric network formed of a plurality of polymer chains.

In a third aspect, the present disclosure is directed to a method ofmanufacturing an article of footwear, e.g. an article of footwear of thesecond aspect. The method comprises the steps of providing an outsole asdisclosed herein, e.g. with respect to the first aspect of thedisclosure, providing an upper for an article of footwear, and securingthe outsole and the upper to each other such that a material comprisinga polymeric network formed of a plurality of polymer chains defines atleast a portion of a ground-facing surface of the outsole. The methodcan be a method comprising the steps of providing an outsole having afirst, ground-facing surface of the outsole and a second surfaceopposing the first surface, wherein the outsole is configured to besecured to an upper for an article of footwear, and wherein a materialcomprising a polymeric network formed of a plurality of polymer chainsdefines at least a portion of the ground-facing first surface of theoutsole; and securing the outsole and the upper to each other such thatthe material defines at least a portion of the ground-facing surface ofthe outsole of the article of footwear.

The method can further comprise the steps of securing the material to afirst side of a backing substrate formed of a second materialcompositionally comprising a thermoplastic; thermoforming the materialsecured to the backing substrate formed of the second material toproduce an outsole face precursor, wherein the outsole face precursorincludes the material secured to the first side of the backingsubstrate; placing the outsole face in a mold; and injecting a thirdmaterial compositionally comprising a thermopolymer onto a second sideof the backing substrate of the outsole face while the outsole face ispresent in the mold to produce an outsole, wherein the outsole comprisesan outsole substrate that includes the backing substrate and the thirdmaterial; and the material secured to the outsole substrate.

In a fourth aspect, the present disclosure is directed to use of amaterial compositionally comprising a polymeric network formed of aplurality of polymer chains to prevent or reduce soil accumulation on anoutsole or an article of footwear. The use involves use of the materialto prevent or reduce soil accumulation on an outsole or an article offootwear on a first surface of outsole, which first surface comprisesthe material, by providing the material on at least a portion of thefirst surface of the outsole, wherein the outsole retains at least 10%less soil by weight as compared to a second outsole which is identicalexcept that the first surface of the second outsole is substantiallyfree of the material comprising a polymeric network formed of aplurality of polymer chains.

The use can be a use of a material compositionally comprising apolymeric network formed of a plurality of polymer chains to prevent orreduce soil accumulation on a first surface of outsole, which firstsurface comprises the material, by providing the material on at least aportion of the first surface of the outsole, wherein the outsole retainsat least 10% less soil by weight as compared to a second outsole whichis identical except that the first surface of the second outsole issubstantially free of the material comprising a polymeric network formedof a plurality of polymer chains. The material can be a material asdescribed above, e.g. with respect to the first aspect of thedisclosure.

In a fifth aspect, the present disclosure is directed to a method ofusing an article of footwear. The method comprises providing an articleof footwear having an upper and an outsole of the present disclosuresecured to the upper, wherein a material comprising a polymeric networkformed of a plurality of polymer chains defines at least a portion of aground-facing surface of the outsole; exposing the material to water totake up at least a portion of the water into the material, forming wetmaterial; pressing the outsole with the wet material onto a groundsurface to at least partially compress the wet material; and lifting theoutsole from the ground surface to release the compression from the wetmaterial. The material can be a material as described above, e.g. withrespect to the first aspect of the disclosure. Additional aspects anddescription of the materials, outsoles, articles, uses and methods ofthe present disclosure can be found below, with particular reference tothe numbered Clauses provided below.

As used herein, the term “outsole” is understood to refer to an outerportion of the sole of an article of footwear. This outer portion of anarticle having the outsole makes up at least a portion of the articlewhich can contact ground during conventional use. In addition to theoutsole, additional sole-type structures such as a midsole, a rigidplate, cushioning, etc., may or may not be present in the article offootwear. As used herein, the terms “article of footwear” and “footwear”are intended to be used interchangeably to refer to the same article.Typically, the term “article of footwear” will be used in a firstinstance, and the term “footwear” may be subsequently used to refer tothe same article for ease of readability.

As used herein, the term “material” is understood to refer to a materialwhich compositionally comprises a polymer. The polymer can be ahydrophilic polymer, i.e., a polymer having a segmental polarity of lessthan 1.5 as determined using the Polymer Segmental PolarityDetermination as described herein. The polymer of the material can bepart of a polymeric network formed of a plurality of polymer chains. Theoverall segment polarity of the polymer network can be less than 1.0.These polymer chains may be formed by copolymerizing one or morerelatively hard, non-polar monomers with one or more relatively soft,polar monomers.

Further, the polymeric network may be formed from a blend of one or morerelatively hard, non-polar hydrophobic polymers and one or morerelatively soft, polar, hydrophilic polymers such that the overallsegment polarity of the polymer blend is less than 1.0. The relativelysoft, hydrophilic polymer can be positioned on the ground-facing surfaceof the outsole or the article of footwear. When present in an outsole ofthe present disclosure, the material defines at least a portion of asurface or side of the outsole. In other words, the material forms atleast part of an outer surface or side of the outsole. The material canbe present as one or more layers disposed on the surface of the outsole,where the layer(s) can be provided as a single continuous segment on thesurface or in multiple discontinuous segments on the surface. Thematerial is not intended to be limited by any application process (e.g.,co-extrusion, injection molding, lamination, spray coating, etc.).

As used herein, the term “polymer” refers to a molecule havingpolymerized units of one or more species of monomer. The term “polymer”is understood to include both homopolymers and copolymers. The term“copolymer” refers to a polymer having polymerized units of two or morespecies of monomers, and is understood to include terpolymers and otherpolymers formed from multiple different monomers. As used herein,reference to “a” polymer or other chemical compound refers one or moremolecules of the polymer or chemical compound, rather than being limitedto a single molecule of the polymer or chemical compound. Furthermore,the one or more molecules may or may not be identical, so long as theyfall under the category of the chemical compound. Thus, for example, “a”polylaurolactam is interpreted to include one or more polymer moleculesof the polylaurolactam, where the polymer molecules may or may not beidentical (e.g., different molecular weights and/or isomers).

The term “ground-facing” refers to the position the element is intendedto be in when the element is present in an article of footwear duringnormal use, i.e., the element is positioned toward the ground duringnormal use by a wearer when in a standing position, and thus can contactthe ground including unpaved surfaces when the footwear is used in aconventional manner, such as standing, walking or running on an unpavedsurface. In other words, even though the element may not necessarily befacing the ground during various steps of manufacturing or shipping, ifthe element is intended to face the ground during normal use by awearer, the element is understood to be ground-facing.

In some circumstances, due to the presence of elements such as tractionelements, the ground-facing surface can be positioned toward the groundduring conventional use but may not necessarily come into contact theground. For example, on hard ground or paved surfaces, the terminal endsof traction elements on the outsole may directly contact the ground,while portions of the outsole located between the traction elements donot. As described in this example, the portions of the outsole locatedbetween the traction elements are considered to be ground-facing eventhough they may not directly contact the ground in all circumstances.

As discussed below, it has been found these outsoles and articles offootwear can prevent or reduce the accumulation of soil on the outsolesduring wear on unpaved surfaces. As used herein, the term “soil” caninclude any of a variety of materials commonly present on a ground orplaying surface and which might otherwise adhere to an outsole orexposed midsole of a footwear article. Soil can include inorganicmaterials such as mud, sand, dirt, and gravel; organic matter such asgrass, turf, leaves, other vegetation, and excrement; and combinationsof inorganic and organic materials such as clay. Additionally, soil caninclude other materials such as pulverized rubber which may be presenton or in an unpaved surface.

While not wishing to be bound by theory, it is believed that thematerial comprising a polymeric network formed of a plurality of polymerchains in accordance with the present disclosure, when sufficiently wetwith water (including water containing dissolved, dispersed or otherwisesuspended materials) can provide compressive compliance and/or expulsionof uptaken water. In particular, it is believed that the compressivecompliance of the wet material, the expulsion of liquid from the wetmaterial, or both in combination, can disrupt the adhesion of soil on orat the outsole, or the cohesion of the particles to each other, or candisrupt both the adhesion and cohesion. This disruption in the adhesionand/or cohesion of soil is believed to be a responsible mechanism forpreventing (or otherwise reducing) the soil from accumulating on thefootwear outsole (due to the presence of the wet material).

This disruption in the adhesion and/or cohesion of soil is believed tobe a responsible mechanism for preventing (or otherwise reducing) thesoil from accumulating on the footwear outsole (due to the presence ofthe wet material). As can be appreciated, preventing soil fromaccumulating on the bottom of footwear can improve the performance oftraction elements present on the outsole during wear on unpavedsurfaces, can prevent the footwear from gaining weight due toaccumulated soil during wear, can preserve ball handling performance ofthe footwear, and thus can provide significant benefits to wearer ascompared to an article of footwear without the material present on theoutsole.

As used herein, the term “weight” refers to a mass value, such as havingthe units of grams, kilograms, and the like. Further, the recitations ofnumerical ranges by endpoints include the endpoints and all numberswithin that numerical range. For example, a concentration ranging from40% by weight to 60% by weight includes concentrations of 40% by weight,60% by weight, and all water uptake capacities between 40% by weight and60% by weight (e.g., 40.1%, 41%, 45%, 50%, 52.5%, 55%, 59%, etc. . . .).

As used herein, the term “providing”, such as for “providing anoutsole”, when recited in the claims, is not intended to require anyparticular delivery or receipt of the provided item. Rather, the term“providing” is merely used to recite items that will be referred to insubsequent elements of the claim(s), for purposes of clarity and ease ofreadability.

As used herein, the terms “preferred” and “preferably” refer to aspectsof the invention that may afford certain benefits, under certaincircumstances. However, other aspects may also be preferred, under thesame or other circumstances. Furthermore, the recitation of one or morepreferred aspects does not imply that other aspects are not useful, andis not intended to exclude other aspects from the scope of the presentdisclosure.

As used herein, the terms “about” and “substantially” are used hereinwith respect to measurable values and ranges due to expected variationsknown to those skilled in the art (e.g., limitations and variability inmeasurements).

As used herein, the terms “at least one” and “one or more of” an elementare used interchangeably, and have the same meaning that includes asingle element and a plurality of the elements, and may also berepresented by the suffix “(s)” at the end of the element. For example,“at least one polyurethane”, “one or more polyurethanes”, and“polyurethane(s)” may be used interchangeably and have the same meaning.

The article of footwear of the present disclosure may be designed for avariety of uses, such as sporting, athletic, military, work-related,recreational, or casual use. Primarily, the article of footwear isintended for outdoor use on unpaved surfaces (in part or in whole), suchas on a ground surface including one or more of grass, turf, gravel,sand, dirt, clay, mud, and the like, whether as an athletic performancesurface or as a general outdoor surface. However, the article offootwear may also be desirable for indoor applications, such as indoorsports including dirt playing surfaces for example (e.g., indoorbaseball fields with dirt infields). As used herein, the terms “at leastone” and “one or more of” an element are used interchangeably, and havethe same meaning that includes a single element and a plurality of theelements, and may also be represented by the suffix “(s)” at the end ofthe element. For example, “at least one polyurethane”, “one or morepolyurethanes”, and “polyurethane(s)” may be used interchangeably andhave the same meaning.

In preferred aspects, the article of footwear is designed use in outdoorsporting activities, such as global football/soccer, golf, Americanfootball, rugby, baseball, running, track and field, cycling (e.g., roadcycling and mountain biking), and the like. The article of footwear canoptionally include traction elements (e.g., lugs, cleats, studs, andspikes) to provide traction on soft and slippery surfaces. Cleats, studsand spikes are commonly included in footwear designed for use in sportssuch as global football/soccer, golf, American football, rugby,baseball, and the like, which are frequently played on unpaved surfaces.Lugs and/or exaggerated tread patterns are commonly included in footwearincluding boots design for use under rugged outdoor conditions, such astrail running, hiking, and military use.

FIGS. 1-4 illustrate an example article of footwear of the presentdisclosure, referred to as an article of footwear 100, and which isdepicted as footwear for use in global football/soccer applications. Asshown in FIG. 1, the footwear 100 includes an upper 110 and an outsole112 as footwear article components, where outsole 112 includes aplurality of traction elements 114 (e.g., cleats) and a materialcomprising a polymeric network formed of a plurality of polymer chains116 at its external or ground-facing side or surface. While many of theembodied footwear of the present disclosure preferably include tractionelements such as cleats, it is to be understood that in other aspects,the incorporation of cleats is optional.

The upper 110 of the footwear 100 has a body 118 which may be fabricatedfrom materials known in the art for making articles of footwear, and isconfigured to receive a user's foot. For example, the upper body 118 maybe made from or include one or more components made from one or more ofnatural leather; a knit, braided, woven, or non-woven textile made inwhole or in part of a natural fiber; a knit, braided, woven or non-woventextile made in whole or in part of a synthetic polymer, a film of asynthetic polymer, etc.; and combinations thereof. The upper 110 andcomponents of the upper 110 may be manufactured according toconventional techniques (e.g., molding, extrusion, thermoforming,stitching, knitting, etc.). While illustrated in FIG. 1 with a genericdesign, the upper 110 may alternatively have any desired aestheticdesign, functional design, brand designators, and the like.

The outsole 112 may be directly or otherwise secured to the upper 110using any suitable mechanism or method. As used herein, the terms“secured to”, such as for an outsole that is secured to an upper, e.g.,is operably secured to an upper, refers collectively to directconnections, indirect connections, integral formations, and combinationsthereof. For instance, for an outsole that is secured to an upper, theoutsole can be directly connected to the upper (e.g., with an adhesive),the outsole can be indirectly connected to the upper (e.g., with anintermediate midsole), can be integrally formed with the upper (e.g., asa unitary component), and combinations thereof.

For example, the upper 110 may be stitched to the outsole 112, or theupper 110 may be glued to the outsole 112, such as at or near a biteline 120 of the upper 110. The footwear 100 can further include amidsole (not shown) secured between the upper 110 and the outsole 112,or can be enclosed by the outsole 112. When a midsole is present, theupper 110 may be stitched, glued, or otherwise attached to the midsoleat any suitable location, such as at or below the bite line 120.

As further shown in FIGS. 1 and 2, the layout of outsole 112 can besegregated into a forefoot region 122, a midfoot region 124, and a heelregion 126. The forefoot region 122 is disposed proximate a wearer'sforefoot, the midfoot region 124 is disposed between the forefoot region122 and the heel region 126, and the heel region 126 is disposedproximate a wearer's heel and opposite the forefoot region 122. Theoutsole 112 may also include a forward edge 128 at the forefoot region122 and a rearward edge 130 at the heel region 126. In addition to theselongitudinal designations, the left/right sides of outsole 112 can alsobe respectively designated by a medial side 132 and a lateral side 134.

Each of these designations can also apply to the upper 110 and moregenerally to the footwear 100, and are not intended to particularlydefine structures or boundaries of the footwear 100, the upper 110, orthe outsole 112. As used herein, directional orientations for anarticle, such as “upward”, “downward”, “top”, “bottom”, “left”, “right”,and the like, are used for ease of discussion, and are not intended tolimit the use of the article to any particular orientation.Additionally, references to “ground-facing surface”, “ground-facingside”, and the like refer to the surface or side of footwear that facethe ground during normal use by a wearer as standing. These terms arealso used for ease of discussion, and are not intended to limit the useof the article to any particular orientation.

The outsole 112 can optionally include a backing plate or 136, which, inthe shown example, extends across the forefoot region 122, the midfootregion 124, and the heel region 126. The backing plate 136 is an examplebacking member or other outsole substrate for use in an article offootwear, and can provide structural integrity to the outsole 112.However, the backing plate 136 can also be flexible enough, at least inparticular locations, to conform to the flexion of a wearer's footduring the dynamic motions produced during wear. For example, as shownin FIGS. 1 and 2, the backing plate 136 may include a flex region 138 atthe forefoot region 122, which can facilitate flexion of the wearer'stoes relative to the foot in active use of the footwear 100.

The backing plate 136 may have a top (or first) surface (or side) 142(best shown in FIGS. 3 and 4), a bottom (or second) surface (or side)144, and a sidewall 146, where the sidewall 146 can extend around theperimeter of the backing plate 136 at the forward edge 128, the rearwardedge 130, the medial side 132, and the lateral side 134. The top surface142 is the region of the backing plate 136 (and the outsole 112 moregenerally) that may be in contact with and secured to the upper 110and/or to any present midsole or insole.

The bottom surface 144 is a surface of the backing plate 136 that iscovered (or at least partially covered) by the material 116 securedthereto, and would otherwise be configured to contact a ground surface,whether indoors or outdoors, if the material 116 were otherwise omitted.The bottom surface 144 is also the portion of outsole 112 that thetraction elements 114 can extend from, as discussed below.

The optional backing plate 136 can be manufactured with one or morelayers, may be produced from any suitable material(s), and can provide agood interfacial bond to the material 116, as discussed below. Examplesof suitable materials for the backing plate 136 include one or morepolymeric materials such as thermoplastic elastomers; thermosetpolymers; elastomeric polymers; silicone polymers; natural and syntheticrubbers; composite materials including polymers reinforced with carbonfiber and/or glass; natural leather; metals such as aluminum, steel andthe like; and combinations thereof.

In particular aspects, when a backing plate 136 is used, the backingplate 136 is manufactured from one or more polymeric materials havingsimilar chemistries to that of the material 116. In other words, thebacking plate and the material can both comprise or consist essentiallyof polymers having the same or similar functional groups, and/or cancomprise or consist essentially of polymers having the same or similarlevels of polarity. For example, the backing plate and the material canboth comprise or consist essentially of one or more polyurethanes (e.g.,thermoplastic polyurethanes), one or more polyamides (e.g.,thermoplastic polyamides), one or more polyethers (e.g., thermoplasticpolyethers), one or more polyesters (e.g., thermoplastic polyesters), orthe like. The similar chemistries can be beneficial for improvingmanufacturing compatibilities between the materials of the material 116and the backing plate 136, and also for improving their interfacial bondstrength. Alternatively, one or more tie layers (not shown) can beapplied between the backing plate 136 and the material 116 in order toimprove their interlayer bonding.

The traction elements 114 may each include any suitable cleat, stud,spike, or similar element configured to enhance traction for a wearerduring cutting, turning, stopping, accelerating, and backward movement.The traction elements 114 can be arranged in any suitable pattern alongthe bottom surface 144 of the backing plate 136. For instance, thetraction elements 114 can be distributed in groups or clusters along theoutsole 112 (e.g., clusters of 2-8 traction elements 114). As best shownin FIGS. 1 and 2, the traction elements 114 can be grouped into acluster 147A at the forefoot region 122, a cluster 147B at the midfootregion 124, and a cluster 147C at the heel region 126. In this example,six of the traction elements 114 are substantially aligned along themedial side 132 of the outsole 112, and the other six traction elements114 are substantially aligned along the lateral side 134 of the outsole112.

The traction elements 114 may alternatively be arranged along theoutsole 112 symmetrically or non-symmetrically between the medial side132 and the lateral side 134, as desired. Moreover, one or more of thetraction elements 114 may be arranged along a centerline of outsole 112between the medial side 132 and the lateral side 134, such as a blade114A, as desired to enhance or otherwise modify performance.

Alternatively (or additionally), traction elements can also include oneor more front-edge traction elements 114, such as one or more blades114B, one or more fins 114C, and/or one or more cleats (not shown)secured to (e.g., integrally formed with) the backing plate 136 at afront-edge region between forefoot region 122 and cluster 147A. In thisapplication, the material 116 can optionally extend across the bottomsurface 144 at this front-edge region while maintaining good tractionperformance.

Furthermore, the traction elements 114 may each independently have anysuitable dimension (e.g., shape and size). For instance, in somedesigns, each fraction element 114 within a given cluster (e.g.,clusters 147A, 147B, and 147C) may have the same or substantially thesame dimensions, and/or each traction element 114 across the entirety ofthe outsole 112 may have the same or substantially the same dimensions.Alternatively, the traction elements 114 within each cluster may havedifferent dimensions, and/or each traction element 114 across theentirety of the outsole 112 may have different dimensions.

Examples of suitable shapes for the traction elements 114 includerectangular, hexagonal, cylindrical, conical, circular, square,triangular, trapezoidal, diamond, ovoid, as well as other regular orirregular shapes (e.g., curved lines, C-shapes, etc. . . . ). Thetraction elements 114 may also have the same or different heights,widths, and/or thicknesses as each other, as further discussed below.Further examples of suitable dimensions for the traction elements 114and their arrangements along the backing plate 136 include thoseprovided in soccer/global football footwear commercially available underthe tradenames “TIEMPO”, “HYPERVENOM”, “MAGISTA”, and “MERCURIAL” fromNike, Inc. of Beaverton, Oreg.

The traction elements 114 may be incorporated into the outsole includingthe optional backing plate 136 by any suitable mechanism such that thetraction elements 114 preferably extend from the bottom surface 144. Forexample, as discussed below, the traction elements 114 may be integrallyformed with the backing plate 136 through a molding process (e.g., forfirm ground (FG) footwear). Alternatively, the outsole or optionalbacking plate 136 may be configured to receive removable tractionelements 114, such as screw-in or snap-in traction elements 114. Inthese aspects, the backing plate 136 may include receiving holes (e.g.,threaded or snap-fit holes, not shown), and the traction elements 114can be screwed or snapped into the receiving holes to secure thetraction elements 114 to the backing plate 136 (e.g., for soft ground(SG) footwear).

In further examples, a first portion of the traction elements 114 can beintegrally formed with the outsole or optional backing plate 136 and asecond portion of the traction elements 114 can be secured withscrew-in, snap-in, or other similar mechanisms (e.g., for SG profootwear). The traction elements 114 may also be configured as shortstuds for use with artificial ground (AG) footwear, if desired. In someapplications, the receiving holes may be raised or otherwise protrudefrom the general plane of the bottom surface 144 of the backing plate136. Alternatively, the receiving holes may be flush with the bottomsurface 144.

The traction elements 114 can be fabricated from any suitable materialfor use with the outsole 112. For example, the traction elements 114 mayinclude one or more of polymeric materials such as thermoplasticelastomers; thermoset polymers; elastomeric polymers; silicone polymers;natural and synthetic rubbers; composite materials including polymersreinforced with carbon fiber and/or glass; natural leather; metals suchas aluminum, steel and the like; and combinations thereof. In aspects inwhich the traction elements 114 are integrally formed with the backingplate 112 (e.g., molded together), the fraction elements 114 preferablyinclude the same materials as the outsole or backing plate 112 (e.g.,thermoplastic materials). Alternatively, in aspects in which thetraction elements 114 are separate and insertable into receiving holesof the backing plate 112, the traction elements 114 can include anysuitable materials that can secured in the receiving holes of thebacking plate 112 (e.g., metals and thermoplastic materials).

The optional backing plate 136 (and more generally, the outsole 112) mayalso include other features other than the traction elements 114 thatcan provide support or flexibility to the outsole and/or for aestheticdesign purposes. For instance, the outsole or backing plate 136 may alsoinclude ridges 148 that may be raised or otherwise protrude from thegeneral plane of the bottom surface 144.

As shown, ridges 148 can extend along the arrangement pathways of thetraction elements 114, if desired. These features (e.g., ridges 148) canbe integrally formed into the outsole or backing plate 136, oralternatively, be removable features that are securable to the backingplate 136. Suitable materials for these features include those discussedabove for the traction elements 114.

The backing plate 136 (and more generally, the outsole 112) may alsoinclude other features such as exaggerated tread patterns, lugs, and thelike, which are configured to contact the ground or playing surface toincrease traction, to enhance performance, or for aesthetic designpurposes. These other features can be present on the outsole in place ofor in addition to the traction elements 114, and can be formed from thesuitable materials discussed above for the traction elements 114.

As further shown in FIGS. 3 and 4, the traction elements 114 can bearranged such that when footwear 100 rests on a flat surface 149, thebottom surface 144 of backing plate 136 and the material 116 are offsetfrom the flat surface 149. This offset is present even when the material116 is fully saturated and swollen, as discussed below. As such, thetraction elements 114 can receive the greatest levels of shear andabrasive contact with surfaces during use, such as by digging into soilduring cutting, turning, stopping, accelerating, backward movements, andthe like. In comparison, the material 116 at its offset location canremain partially protected from a significant portion of these shear andabrasive conditions, thereby preserving its integrity during use.

FIG. 5 is an expanded sectional view of the material 116 and the bottomsurface 144 of the backing plate 136 at one of the traction elements114. In this shown example, the traction element 114, which can berepresentative of one or more of the other traction elements 114, isintegrally molded with the backing plate 136 and includes a shaft 150that protrudes downward beyond the bottom surface 144 and the material116. The shaft 150 itself may include an outer side surface 152 and aterminal edge 154. The terminal edge 154 of the shaft 150 is the distalend of the traction element 114, opposite from the bottom surface 144,and is the portion of the traction element 114 that can initiallycontact and penetrate into a playing or ground surface.

As mentioned above, the traction element 114 may have any suitabledimensions and shape, where the shaft 150 (and the outer side surface152) can correspondingly have rectangular, hexagonal, cylindrical,conical, circular, square, triangular, trapezoidal, diamond, ovoid, aswell as other regular or irregular shapes (e.g., curved lines, C-shapes,etc. . . . ). Similarly, the terminal edge 154 can have dimensions andsizes that correspond to those of the outer side surface 152, and can besubstantially flat, sloped, rounded, and the like. Furthermore, in someaspects, the terminal edge 154 can be substantially parallel to thebottom surface 144 and/or the material 116.

Examples of suitable average lengths 156 for each shaft 150 relative tobottom surface 144 range from 1 millimeter to 20 millimeters, from 3millimeters to 15 millimeters, or from 5 millimeters to 10 millimeters,where, as mentioned above, each traction element 114 can have differentdimensions and sizes (i.e., the shafts 150 of the various tractionelements 114 can have different lengths).

In the example shown in FIGS. 1-5, the material 116 is present on theentire bottom surface 144 of the backing plate 136 between (and notincluding) the traction elements 114. For instance, as shown in FIG. 5,the material 116 can cover the bottom surface 144 at locations aroundthe shaft 150 of each traction element 114, such that material 116 doesnot cover the outer side surface 152 or the terminal edge 154 of thetraction element 114, other than optionally at a base region 158 of theshaft 150. This can preserve the integrity of the material 116 andpreserve traction performance of the traction elements 114. In someaspects, the material 116 does not cover or contact any portion of theouter side surface 152 of the shaft 150. In other aspects, the baseregion 158 that the material 116 (in a dry state) covers and contactsthe outer side surface 152 is less than 25%, less than 15%, or less than10% of the length of the shaft 150, as an average distance measured fromthe bottom surface 144 at the traction element 114.

As can be seen in FIG. 5, the material 116 can be provided in a form ofa thin film to minimize or otherwise reduce its impact on the tractionelements 114. Examples of suitable average thicknesses for the materialor film 116 in a dry state (referred to as a dry-state materialthickness 160) range from 0.025 millimeters to 5 millimeters, from 0.5millimeters to 3 millimeters, from 0.25 millimeters to 1 millimeter,from 0.25 millimeters to 2 millimeters, from 0.25 millimeters to 5millimeters, from 0.15 millimeters to 1 millimeter, from 0.15millimeters to 1.5 millimeters, from 0.1 millimeters to 1.5 millimeters,from 0.1 millimeters to 2 millimeters, from 0.1 millimeters to 5millimeters, from 0.1 millimeters to 1 millimeter, or from 0.1millimeters to 0.5 millimeters. As depicted, the thicknesses for thematerial 116 are measured between the interfacial bond at the bottomsurface 144 of the backing plate 136 and an exterior surface of thematerial 116 (referred to as a material surface 162).

In some alternative aspects, the material 116 can also (oralternatively) be present on one or more regions of the tractionelements 114. For example, the material can be present at an exteriorsurface of the traction elements 114. These aspects can be beneficial,for example, in applications where the traction element 114 has acentral base with multiple shafts 150 that protrude from the peripheryof the central base. In such aspects, the material 116 can be present onat least the central base of the traction element 114. Furthermore, forsome applications, the material 116 may also cover the entirety of oneor more of the traction elements 114 (e.g., on the shaft 150).

Presence of the material 116 on the ground-facing side of outsole 112(i.e., on bottom surface 144) allows the material 116 to come intocontact with soil, including wet soil during use, which is believed toenhance the soil-shedding performance for the footwear 100, as explainedbelow. However, the material 116 can also optionally be present on oneor more locations of the sidewall 146 of the backing plate 136.

As briefly mentioned above, the material 116 compositionally includes aa polymeric network formed of a plurality of polymer chains. Thepresence of the polymeric network in the material can allow the material116 to absorb or otherwise take up water. For example, the material cantake up water from an external environment (e.g., from mud, wet grass,presoaking, and the like).

As used herein, the term “compliant” refers to the stiffness of anelastic material, and can be determined by the storage modulus of thematerial. Generally, when the polymeric network of the material is acrosslinked polymeric network (e.g., includes physical crosslinks,covalent crosslinks, or both), the lower the degree of crosslinking inthe polymeric network, or the greater the distance between crosslinks inthe polymeric network, the more compliant the material will be. Inparticular aspects, when the material comprises a crosslinked polymericnetwork, it is believed that this uptake of water by the material 116can cause the crosslinked polymeric network to expand and stretch underthe pressure of the received water, while retaining its overallstructural integrity through its crosslinking. This stretching andexpansion of the polymeric network can cause the material 116 to swelland become more compliant (e.g., compressible, expandable, andstretchable).

In aspects where the material swells, the swelling of the material 116can be observed as an increase in material thickness from the dry-statethickness 160 of the material 116 (shown in FIG. 5), through a range ofintermediate-state thicknesses (e.g., thickness 163, shown in FIG. 5A)as additional water is absorbed, and finally to a saturated-statethickness 164 (shown in FIG. 5B), which is an average thickness of thematerial 116 when fully saturated with water. For example, thesaturated-state thickness 164 for the fully saturated material 114 canbe greater than 150%, greater than 200%, greater than 250%, greater than300%, greater than 350%, greater than 400%, or greater than 500%, of thedry-state thickness 160 for the same material 116.

In some aspects, the saturated-state thickness 164 for the fullysaturated material 114 range from 150% to 500%, from 150% to 400%, from150% to 300%, or from 200% to 300% of the dry-state thickness 160 forthe same material 116. Examples of suitable average thicknesses for thematerial 116 in a wet state (referred to as a saturated-state thickness164) range from 0.2 millimeters to 10 millimeters, from 0.2 millimetersto 5 millimeters, from 0.2 millimeters to 2 millimeters, from 0.25millimeters to 2 millimeters, or from 0.5 millimeters to 1 millimeter.

In particular aspects, the material 116 can quickly take up water thatis in contact with the material 116. For instance, the material 116 cantake up water from mud and wet grass, such as during a warmup periodprior to a competitive match. Alternatively (or additionally), thematerial 116 can be pre-conditioned with water so that the material 116is partially or fully saturated, such as by spraying or soaking theoutsole 112 with water prior to use.

The total amount of water that the material 116 can take up depends on avariety of factors, such as its composition (e.g., its hydrophilicity),its cross-linking density, its thickness, and its interfacial bond tothe backing plate 136 when a backing plate is present. For example, itis believed that a material comprising a polymeric network having ahigher level of hydrophilicity and a lower level of cross-linkingdensity can increase the water uptake capacity of the material 116. Onthe other hand, the interfacial bond between the material 116 and thebottom surface 144 of the backing plate 136 (when a backing plate 136 isused) can potentially restrict the swelling of the material 116 due toits relatively thin dimensions. Accordingly, as described below, thewater uptake capacity and the swelling capacity of the material 116 candiffer between the material 116 in a neat film state (isolated film byitself) and the material 116 as present on a backing plate 136.

The water uptake capacity and the water uptake rate of the material 116are dependent on the size and shape of its geometry, and are typicallybased on the same factors. However, it has been found that, to accountfor part dimensions when measuring water uptake capacity, it is possibleto derive an intrinsic, steady-state material property. Therefore,conservation of mass can be used to define the ratio of water weightabsorbed to the initial dry weight of the material 116 at very long timescales (i.e. when the ratio is no longer changing at a measurable rate).

Conversely, the water uptake rate is transient and can be definedkinetically. The three primary factors for water uptake rate for amaterial 116 present at a surface of an outsole given part geometryinclude time, thickness, and the exposed surface area available fortaking up water. Once again, the weight of water taken up can be used asa metric of water uptake rate, but the water flux can also be accountedfor by normalizing by the exposed surface area. For example, a thinrectangular film can be defined by 2×L×W, where L is the length of oneside and W is the width. The value is doubled to account for the twomajor surfaces of the film, but the prefactor can be eliminated when thefilm has a non-absorbing, structural layer secured to one of the majorsurfaces (e.g., with an outsole backing plate).

Normalizing for thickness and time can require a more detailed analysisbecause they are coupled variables. Water penetrates deeper into thefilm as more time passes in the experiment, and therefore, there is morefunctional (e.g., absorbent) material available at longer time scales.One dimensional diffusion models can explain the relationship betweentime and thickness through material properties, such as diffusivity. Inparticular, the weight of water taken up per exposed surface area shouldyield a straight line when plotted against the square root of time.

However, several factors can occur where this model does not representthe data well. First, at long times absorbent materials become saturatedand diffusion kinetics change due to the decrease in concentrationgradient of the water. Second, as time progresses the material can beplasticized to increase the rate of diffusion, so once again the modeldo longer represents the physical process. Finally, competing processescan dominate the water uptake or weight change phenomenon, typicallythrough surface phenomenon such as physisorption on a rough surface dueto capillary forces. This is not a diffusion driven process, and thewater is not actually be taken up into the film.

Even though the material 116 can swell as it takes up water andtransitions between the different material states with correspondingthicknesses 160, 163, and 164, the saturated-state thickness 164 of thematerial 116 preferably remains less than the length 156 of the tractionelement 114. This selection of the material 116 and its correspondingdry and saturated thicknesses ensures that the traction elements 114 cancontinue to provide ground-engaging traction during use of the footwear100, even when the material 116 is in a fully swollen state. Forexample, the average clearance difference between the lengths 156 of thetraction elements 114 and the saturated-state thickness 164 of thematerial 116 is desirably at least 8 millimeters. For example, theaverage clearance distance can be at least 9 millimeters, 10millimeters, or more.

As also mentioned above, in addition to swelling, the compliance of thematerial 116 may also increase from being relatively stiff (i.e.,dry-state) to being increasingly stretchable, compressible, andmalleable (i.e., wet-state). The increased compliance accordingly canallow the material 116 to readily compress under an applied pressure(e.g., during a foot strike on the ground), and in some aspects, toquickly expel at least a portion of its retained water (depending on theextent of compression). While not wishing to be bound by theory, it isbelieved that this compressive compliance alone, water expulsion alone,or both in combination can disrupt the adhesion and/or cohesion of soilat outsole 112, which prevents or otherwise reduces the accumulation ofsoil on outsole 112.

In addition to quickly expelling water, in particular examples, thecompressed material 116 is capable of quickly re-absorbing water whenthe compression is released (e.g., liftoff from a foot strike duringnormal use). As such, during use in a wet or damp environment (e.g., amuddy or wet ground), the material 116 can dynamically expel andrepeatedly take up water over successive foot strikes, particularly froma wet surface. As such, the material 116 can continue to prevent soilaccumulation over extended periods of time (e.g., during an entirecompetitive match), particularly when there is ground water availablefor re-uptake.

FIGS. 6-9 illustrate an example method of using footwear 100 with amuddy or wet ground 166, which depict one potential mechanism by whichthe materials comprising polymeric networks as disclosed herein canprevent or reduce soil accumulation on the outsole 112. It is known thatthe soil of the ground 166 can accumulate on an outsole (e.g., betweenthe traction elements) during normal athletic or casual use, inparticular when the ground 166 is wet. The soil is believed toaccumulate on the outsole due to a combination of adhesion of the soilparticles to the surface of the outsole and cohesion of the soilparticles to each other. In order to break these adhesive/cohesiveforces, the soil particles need to be subjected to stresses high enoughto exceed their adhesive/cohesive activation energies. When this isachieved, the soil particles can then move or flow under the appliedstresses, which dislodge or otherwise shed portions of the soil from theoutsole.

However, during typical use of cleated footwear, such as duringcompetitive sporting events (e.g., global football/soccer matches,golfing events, and American football games), the actions of walking andrunning are not always sufficient to dislodge the soil from the outsole.This can result in the soil sticking to the outsoles, particularly inthe interstitial regions where compaction forces in the normal directionare maximized between the individual traction elements. As can beappreciated, this soil can quickly accumulate to increase the weight ofthe footwear and reduce the effectiveness of the traction elements(e.g., because they have less axial or normal extent capable of engagingwith the ground 166), each of which can have a significant impact onathletic performance.

The incorporation of the material 116 to a surface or side of theoutsole 112 (e.g., a ground-facing surface or side of the outsole)however, is believed to disrupt the adhesion and/or cohesion of soil atthe outsole 112, thereby reducing the adhesive/cohesive activationenergies otherwise required to induce the flow of the soil particles. Asshown in FIG. 6, the footwear 100 can be provided in a pre-conditioned(e.g., pre-wet) state where the material 116 is partially or fullysaturated with water. This can be accomplished in a variety of manners,such as spraying the outsole 112 with water, soaking the outsole 112 inwater, or otherwise exposing the material 116 to water in a sufficientamount for a sufficient duration. Alternatively (or additionally), whenwater or wet materials are present on the ground 166, footwear 100 canbe used in a conventional manner on the ground 166 until the material116 absorbs a sufficient amount of water from the ground 166 or wetmaterials to reach its pre-conditioned state.

During a foot strike, the downward motion of the footwear 100(illustrated by arrow 168) causes the traction element 114 to contactthe ground 166. As shown in FIG. 7, the continued applied pressure ofthe foot strike can cause the fraction element 114 to penetrate into thesofter soil of the ground 166 until the material surface 162 of thematerial 116 contacts the ground 166. As shown in FIG. 8, furtherapplied pressure of the foot strike can press the material 116 into theground 166, thereby at least partially compressing the material 116under the applied pressure (illustrated by arrows 170).

As can be seen, this compression of the material 116 into the soil ofthe ground 166 typically compacts the soil, increasing the potential forthe soil particles to adhere to outsole 112 and to cohesively adhere toeach other (clumping together). However, the compression of the material116 may also expel at least a portion of its uptaken water into the soilof the ground 166 (illustrated by arrows 172). It is believed that asthe water is expelled through the material surface 162 of the material116, the pressure of the expelled water can disrupt the adhesion of thesoil to the material surface 162 at this interface.

Additionally, once expelled into the soil, it is also believed that thewater may also modify the rheology of the soil adjacent to the materialsurface 162 (e.g., watering down the soil to a relatively muddier orwetter state). This is believed to essentially spread out the soilparticles in the water carrier and weaken their cohesive forces (e.g.,mechanical/ionic/hydrogen bonds). Each of these mechanisms from theexpelled water is believed to lower the required stresses need todisrupt the adhesion of the soil from the outsole 112. As such, thestresses typically applied during athletic performances (e.g., whilerunning, handling the ball with the footwear, and kicking the ball) canexceed the cohesive/adhesive activation energies more frequently.

As shown in FIG. 9, when the footwear 100 is lifted following the footstrike (illustrated by arrow 174), it is believed that the compressionapplied to the material 116 is released, and so the material 116 can befree to expand. In some examples, it has been found that, when theoutsole 112 is lifted apart from the ground 166, a thin water layer canremain in contact with the material surface 162, which can quicklyre-uptake into the material 116. This quick re-uptake of water from thematerial surface 162 after compression is removed (e.g., within about 1,2, or 5 seconds) can quickly swell the material 116 back at leastpartially to its previously-swelled state (depending on the amount ofwater re-absorbed), as illustrated by arrows 176.

This cyclic compression and expansion from repeated, rapid, and/orforceful foot strikes during use of the footwear 100 can alsomechanically disrupt the adhesion of any soil still adhered to thematerial surface 162, despite the relatively small thickness of thematerial 116 in any of its various states of water saturation (e.g.,partially to fully saturated). In particular, the increased complianceis believed, under some conditions, to lead to inhomogeneous shearstates in the soil when compressed in the normal or vertical direction,which can also lead to increased interfacial shear stresses and adecrease in soil accumulation.

In some aspects, the material 116 can swell during water re-uptake (andalso during initial uptake) in a non-uniform manner. In such aspects,the uptaken water may tend to travel in a path perpendicular to thematerial surface 162, and so may not migrate substantially in atransverse direction generally in the plane of the material 116 onceabsorbed. This uneven, perpendicular water uptake and relative lack oftransverse water intra-material transport can form an irregular or roughtexture or small ridges on the material surface 162. The presence ofthese small ridges on the irregular material surface 162 from thenon-uniform swelling are also believed to potentially further disruptthe adhesion of the soil at the material surface 162, and thus mayloosen the soil and further promote soil shedding. The uneven, ridgedmaterial surface 162 can also be seen in the photograph of FIG. 19 of anexemplary water-saturated material 116 according to the presentdisclosure.

In addition to the uptake, compression, expulsion, re-uptake, andswelling cycle discussed above, the increased compliance of the material116, for example elongational compliance in the longitudinal direction,may allow the material 116 to be more malleable and stretchable whenswelled. For example, as illustrated in FIG. 10, during a foot rotationin a foot strike (e.g., as the foot generally rolls from heel to toeduring a stride), the outsole 112 and the material 116 arecorrespondingly flexed (e.g., inducing compression forces illustrated byarrows 170).

The increased elongation or stretchiness of the material 116 whenpartially or fully saturated with water can increase the extent that thematerial 116 stretches during this flexing, which can induce additionalshear on any soil adhered to the material surface 162. As illustrated, arolling ground strike creates a curved outsole 112 and a curvedcompressed material 116, which can cause water to be expelled therefromand transverse material stretching forces being induced to pull apartand shed the soil. The compression forces (illustrated by arrows 170) onthe material 116, which can help to expel the water can be particularlystrong at points of contact with the ground 166 and/or where the radiusof curvature of the curved outsole 112/curved material 116 is relativelysmall or at its minimum.

The foregoing properties of the material 116 related tocompression/expansion compliance and the elongation compliance arebelieved to be closely interrelated, and they can depend on the samematerial 116 properties (e.g., a hydrophilic material able to able torapidly take up and expel relatively large amounts of water compared tothe material size or thickness). A distinction is in their mechanismsfor preventing soil accumulation, for example surface adhesiondisruption versus shear inducement. The water re-uptake is believed topotentially act to quickly expand or swell the material 116 after beingcompressed to expel water. Rapid water uptake can provide a mechanismfor replenishing the material 116 water content between foot strikes.Rapid replenishment of the material 116 water content can restore thematerial 116 to its compliant state, returning it to a state wherestretching and shearing forces can contribute to debris shedding. Inaddition, replenishment of the material 116 water content can permitsubsequent water expulsion to provide an additional mechanism forpreventing soil accumulation (e.g., application of water pressure andmodification of soil rheology). As such, the water absorption/expulsioncycle can provide a unique combination for preventing soil accumulationon the outsole 112 of the footwear 100.

In addition to being effective at preventing soil accumulation, thematerial 116 has also been found to be sufficiently durable for itsintended use on the ground-contacting side of the outsole 112.Durability is based in part on the nature and strength of theinterfacial bond of the material 116 to the bottom surface 144 of thebacking plate 136, as well as the physical properties of the material116 itself. For many examples, during the useful life of the material116, the material 116 may not delaminate from the backing plate 136, andit can be substantially abrasion- and wear-resistant (e.g., maintainingits structural integrity without rupturing or tearing).

In various aspects, the useful life of the material 116 (and the outsole112 and footwear 100 containing it) is at least 10 hours, 20 hours, 50hours, 100 hours, 120 hours, or 150 hours of wear. For example, in someapplications, the useful life of the material 116 ranges from 20 hoursto 120 hours. In other applications, the useful life of the material 116ranges from 50 hours to 100 hours of wear.

Interestingly, for many examples, the dry and wet states of the material116 can allow the material 116 to dynamically adapt in durability toaccount for dry and wet surface play. For example, when used on a dryground 166, the material 116 can also be dry, which renders it stifferand more wear resistant. Alternatively, when used on wet ground 166 orwhen wet material is present on a dry ground 166, the material 116 canquickly take up water to achieve a partially or fully saturatedcondition, which may be a swollen and/or compliant state. However, thewet ground 166 imposes less wear on the swollen and compliant material116 compared to dry ground 166. As such, the material 116 can be used ina variety of conditions, as desired. Nonetheless, the footwear 100 andthe outsole 112 are particularly beneficial for use in wet environments,such as with muddy surfaces, grass surfaces, and the like.

While the material 116 is illustrated above in FIGS. 1-4 as extendingacross the entire bottom surface 144 of the outsole 112 of the footwear100, in alternative aspects, the material 116 can alternatively bepresent as one or more segments that are present at separate, discretelocations on the bottom surface 144 of the outsole 112. For instance, asshown in FIG. 11, the material 116 can alternatively be present as afirst segment 116A secured to the bottom surface 144 at the forefootregion 122, such as in the interstitial region between the tractionelements 114 of cluster 147A; a second segment 116B secured to thebottom surface 144 at the midfoot region 124, such as in theinterstitial region between the fraction elements 114 of cluster 147B;and/or a third segment 116C secured to the bottom surface 144 at theheel region 126, such as in the interstitial region between the fractionelements 114 of cluster 147C. In each of these examples, the remainingregions of the bottom surface 144 can be free of the material 116.

In some arrangements, the material 116 is present as one or moresegments secured to the bottom surface 144 at a region 178 between theclusters 147A and 147B, at a region 180 between the clusters 147B and147C, or both. For example, the material 116 may include a first segmentpresent on the bottom surface 144 that encompasses the locations ofsegment 116A, the region 178, and segment 116B as well at the locationof region 178; and a second segment corresponding to the segment 116B(at the cluster 147C). As also shown in FIG. 11, the segments of thematerial 116 (e.g., segments 116A, 116B, and 116C) can optionally havesurface dimensions that conform to the overall geometry of the backingplate 136, such as to conform to the contours of the ridges 148, thetraction elements 114, and the like.

In another arrangement, the bottom surface 144 includes a front edgeregion 182 between the front edge 128 and the cluster 147A (andoptionally include a front portion of the cluster 147A) that is free ofthe material 116. As some of the examples of the material 116 may beslippery when partially or fully saturated, having the material 116present in the front edge region 182 of the bottom surface 144 canpotentially impact traction and ball handling during sports.Furthermore, soil accumulation is typically most prominent in theinterstitial regions of the clusters 147A, 147B, and 147C, in comparisonto the front edge 128.

Furthermore, the optional backing plate 136 can also include one or morerecessed pockets, such as a pocket 188 shown in FIG. 12, in which thematerial 116 or a sub-segment of the material 116 can reside. This canpotentially increase the durability of the material 116 by protecting itfrom lateral delamination stresses. For instance, the backing plate 136can include a pocket 188 in the interstitial region of cluster 147C,where the sub-segment 116C of the material 116 can be secured to thebottom surface 144 within the pocket 188. In this case, the dry-statethickness 160 of the material 116 can vary relative to a depth 190 ofthe pocket 188.

In some aspects, the depth 190 of the pocket 188 can range from 80% to120%, from 90% to 110%, or from 95% to 105% of the dry-state thickness160 of the material 116. Moreover, in aspects in which the backing plate136 includes multiple pockets 188, each pocket 188 may have the samedepth 190 or the depths 190 may independently vary as desired. As can beappreciated, the increased bonding of the material 116 due to therecessed pocket 188 can potentially reduce the swelling of the material116 when partially or fully saturated. However, a significant portion ofthe material 116 can be offset enough from the walls of the pocket 188such that these interfacial bonds (relative to the dry-state thickness160) will minimally affect the swelling and water-absorbing performanceof the material 116.

FIG. 13 illustrates an alternative design for the engagement between thematerial 116 and the bottom surface 144. In this case, the backing plate136 can include one or more recessed indentations 192 having anysuitable pattern(s), and in which portions of the material 116 extendinto the indentations 192 to increase the interfacial bond surface areabetween the material 116 and the bottom surface 144 of the backing plate136. For example, the indentations 192 can be present as one or moregeometrically-shaped holes (e.g., circular, rectangular, or othergeometric shapes) or irregularly-shaped holes in the backing plate 136,one or more trenches or channels extending partially or fully along thebacking plate 136 (in the lateral, longitudinal, or diagonaldirections), and the like.

In these aspects, the material 116 can have two (or more) thicknessesdepending on whether a given portion of the material 116 extends intoone of the indentations. For ease of discussion and readability, thedry-state thickness 160 of the material 116, as used herein, refers to aportion of the material 116 (in a dry state) that does not extend intoone of the indentations, such as at locations 194. As such, thedry-state thickness 160 shown in FIG. 13 is the same as the dry-statethickness 160 shown above in FIG. 5.

Each indentation 192 may independently have a depth 196, which can rangefrom 1% to 200%, from 25% to 150%, or from 50% to 100% of the dry-statethickness 160 of the material 116. In these locations, the dry-statethickness of the material 116 is the sum of the dry-state thickness 160and the depth 196. An interesting result of this arrangement is that thematerial 116 can potentially swell to different partially or fullysaturated-state thicknesses 164. In particular, because the amount thatthe material 116 swells depends on the initial, dry-state thickness ofthe material 116, and because the portions of the material 116 at theindentations 192 have greater dry-state thicknesses compared to theportions of the material 116 at locations 194, this can result in anon-planar swelling of the material 116, as depicted by broken lines198. The particular dimensions of the non-planar swelling can varydepending on the relative dry-state thicknesses of the material 116, thedepth 196 of the indentations 192, the extent of saturation of thematerial 116, the particular composition of the material 116, and thelike.

FIG. 14 illustrates a variation on the indentations 192 shown above inFIG. 13. In the design shown in FIG. 14, the indentations 192 can alsoextend in-plane with the backing plate 136 to form locking members 200(e.g., arms or flanged heads). This design can also be produced withco-extrusion or injection molding techniques, and can further assist inmechanically locking the material 116 to the backing plate 136.

As discussed above, the outsole 112 with the material 116 isparticularly suitable for use in global football/soccer applications.However, the material 116 can also be used in combination with othertypes of footwear 100, such as for articles of footwear 100 for golf(shown in FIG. 15), for baseball (shown in FIG. 16), and for Americanfootball (shown in FIG. 17), each of which can include traction elements114 as cleats, studs, and the like.

FIG. 15 illustrates an aspect in which the material 116 is positioned onone or more portions of the outsole 112 and/or traction elements 114 inan article of golf footwear 100. In some cases, the material 116 ispresent on one or more locations of the ground-facing surface of theoutsole 112 except the traction elements 114 (e.g., a non-cleatedsurface, such as generally illustrated in FIG. 1 for the globalfootball/soccer footwear 100). Alternatively or additionally, thematerial 116 can be present as one or more material segments 116D on oneor more surfaces between tread patterns 202 on ground-facing surface ofthe outsole 112.

Alternatively or additionally, the material 116 can be incorporated ontoone or more surfaces of the traction elements 114. For example, thematerial 116 can also be on a central region of traction element 114between the shafts/spikes 150A, such as a surface opposing the areawhere the traction element 114 is mounted to the outsole 112 backingplate 136. In many traction elements used for golf footwear, thetraction element 114 has a generally flat central base region 158A and aplurality of shafts/spikes 150A arranged around the perimeter of thecentral region 158A. In such traction elements, the material 116 can belocated on the generally flat central base region 158A.

In such aspects, remaining regions of the outsole 112 can be free of thematerial 116. For example, the cleats 114 having material 116 can beseparate components that can be secured to the outsole 112 (e.g.,screwed or snapped in), where the outsole 112 itself can be free of thematerial 116. In other words, the material-covered cleats 114 can beprovided as components for use with standard footwear not otherwisecontaining the 116 (e.g., golf shoes or otherwise).

FIG. 16 illustrates an aspect in which the material 116 is positioned onone or more portions of the outsole 112 in an article of baseballfootwear 100. In some cases, the material 116 is present on one or morelocations of the ground-facing surface of the outsole 112 except thecleats 114 (e.g., a non-cleated surface, such as generally illustratedin FIG. 1 for the global football/soccer footwear 100). Alternatively oradditionally, the material 116 can be present as one or more materialsegments 116D on one or more recessed surfaces 204 in the ground-facingsurface of the outsole 112, which recessed surfaces 204 can include thecleats 114 therein (e.g., material 116 is located only in one or more ofthe recessed surfaces 204, but not substantially on the cleats).

FIG. 17 illustrates an aspect in which the material 116 is positioned onone or more portions of the outsole 112 in an article of Americanfootball footwear 100. In some cases, the material 116 is present on oneor more locations of the ground-facing surface of the outsole 112 exceptthe cleats 114 (e.g., a non-cleated surface, such as generallyillustrated in FIG. 1 for the global football/soccer footwear 100).Alternatively or additionally, the material 116 can be present as one ormore material segments 116D on one or more recessed surfaces 204 in theground-facing surface of the outsole 112, which recessed surfaces 204can include the cleats 114 therein (e.g., material 116 is located onlyin one or more of the recessed surfaces 204, but not substantially onthe cleats).

FIG. 18 illustrates an aspect in which the material 116 is positioned onone or more portions of the outsole 112 in an article of hiking footwear100 (e.g., hiking shoes or boots). As illustrated, the traction elements114 are in the form of lugs 114D which are integrally formed with andprotrude from the outsole 112 bottom surface 144. In some cases, thematerial 116 is present on one or more locations of the bottom surface144 of the outsole 112 except the lugs 114D. For example, the material116 can be located on recessed surfaces 204 between adjacent lugs 114D(e.g., but not substantially on the lugs 114D).

The foregoing discussions of footwear 100 and outsole 112 have been madeabove in the context of footwear having traction elements (e.g.,traction elements 114), such as cleats, studs, spikes, lugs, and thelike. However, footwear 100 having material 116 can also be designed forany suitable activity, such as running, track and field, rugby, cycling,tennis, and the like. In these aspects, one or more segments of thematerial 116 are preferably located in interstitial regions between thetraction elements, such as in the interstitial grooves of a running shoetread pattern.

As discussed above, the material of the present disclosure, such as thematerial 116 for use with outsole 112 (and footwear 100), cancompositionally include a polymeric network which allows the material totake up water. As used herein, the terms “take up”, “taking up”,“uptake”, “uptaking”, and the like refer to the drawing of a liquid(e.g., water) from an external source into the material, such as byabsorption, adsorption, or both. Furthermore, as briefly mentionedabove, the term “water” refers to an aqueous liquid that can be purewater, or can be an aqueous carrier with lesser amounts of dissolved,dispersed or otherwise suspended materials (e.g., particulates, otherliquids, and the like).

The ability of the material (e.g., the material 116) when used on anoutsole to uptake water and to correspondingly swell and increase incompliance can reflect its ability to prevent soil accumulation duringuse with an article of footwear (e.g., footwear 100). As discussedabove, when the material takes up water (e.g., through absorption,adsorption, capillary action, etc. . . . ), the water taken up by thematerial transitions the material from a dry, relatively more rigidstate to a partially or fully saturated state that is relatively morecompliant. When the material is then subjected to an application ofpressure, either compressive or flexing, the material can reduce involume, such as to expel at least a portion of its water.

This expelled water is believed to reduce the adhesive/cohesive forcesof soil particles at the outsole, which taken alone, or more preferablyin combination with the material compliance, can prevent or otherwisereduce soil accumulation at the outsole. Accordingly, the material canundergo dynamic transitions during and between foot strikes, such aswhile a wearer is running or walking, and these dynamic transitions canresult in forces which dislodge accumulated soil or otherwise reducesoil accumulation on the outsole as well.

Based on the multiple interacting mechanisms involved in reducing orpreventing soil accumulation on the outsoles of the present disclosure,it has been found that different properties of the material used to formall or a portion of an outsole can be used to select the desiredperformance benefits needed, such as, for example, preventing orreducing soil adherence to the outsoles or increasing compliance ordurability of the material. For instance, the article of footwear of thepresent disclosure (e.g., the footwear 100), the outsole (e.g., theoutsole 114), and the material (e.g., the material 116) can becharacterized in terms of material's water uptake capacity and rate,swelling capacity, contact angle when wet, coefficient of friction whenwet and dry, reduction in storage modulus from dry to wet, reduction inglass transition temperature from dry to wet, and the like.

The terms “Footwear Sampling Procedure”, “Co-Extruded Film SamplingProcedure”, “Neat Film Sampling Procedure”, “Neat Material SamplingProcedure”, “Water Uptake Capacity Test”, “Water Uptake Rate Test”,“Swelling Capacity Test”, “Contact Angle Test”, “Coefficient of FrictionTest”, “Storage Modulus Test”, “Glass Transition Temperature Test”,“Impact Energy Test”, and “Soil Shedding Footwear Test” as used hereinrefer to the respective sampling procedures and test methodologiesdescribed in the Property Analysis And Characterization Proceduresection below. These sampling procedures and test methodologiescharacterize the properties of the recited materials, outsoles,footwear, and the like, and are not required to be performed as activesteps in the claims.

It is to be understood that any of the Tests disclosed herein can beconducted using any of the Sampling Procedures disclosed herein todetermine a property of an outsole or a property which can be attributedto an outsole or an outsole of an article of footwear based on ameasurement made in a simulated environment (e.g., using a sampleprepared according to the Co-extruded Film Sampling Procedure, the NeatFilm Sampling Procedure, or the Neat Material Sampling Procedure). Inother words, a measurement obtained on a neat material can be attributedto an outsole comprising the material where the material defines atleast a portion of a surface or side of the outsole. Additionally, ameasurement made in a simulated environment can be used to select thedesired performance property for an outsole comprising the materialwhere the material defines at least a portion of a surface or side ofthe outsole.

For example, in some aspects, the material (e.g., material present as asample of a portion of an outsole prepared according to the FootwearSampling Procedure, the outsole having the material present at ordefining a side or surface of the outsole from which the sample wastaken) has a water uptake capacity at 24 hours greater than 40% byweight, as characterized by the Water Uptake Capacity Test with theFootwear Sampling Procedure, each as described below. In some aspects,it is believed that if a particular outsole is not capable of taking upgreater than 40% by weight in water within a 24-hour period, either dueto its water uptake rate being too slow, or its ability to take up wateris too low (e.g., due to its thinness, not enough material may bepresent, or the overall capacity of the material to take up water is toolow), then the outsole may not be effective in preventing or reducingsoil accumulation.

In further aspects, the material (including a side or surface of anoutsole formed of the material) has a water uptake capacity at 24 hoursgreater than 50% by weight, greater than 100% by weight, greater than150% by weight, or greater than 200% by weight. In other aspects,outsole has a water uptake capacity at 24 hours less than 900% byweight, less than 750% by weight, less than 600% by weight, or less than500% by weight.

In particular aspects, the material (including a side or surface of anoutsole formed of the material) has a water uptake capacity at 24 hoursranging from 40% by weight to 900% by weight. For example, the outsolecan have a water uptake capacity ranging from 100% by weight to 900% byweight, from 100% by weight to 750% by weight, from 100% by weight to700% by weight, from 150% by weight to 600% by weight, from 200% byweight to 500% by weight, or from 300% by weight to 500% by weight.

These water uptake capacities are determined by the Water UptakeCapacity Test with the Footwear Sampling Procedure, and can apply tosamples taken at any suitable representative location along the outsole,where the samples may be acquired pursuant to the Footwear SamplingProcedure. In some cases, samples can be taken from one or more of theforefoot region, the midfoot region, and/or the heel region; from eachof the forefoot region, the midfoot region, and the heel region; fromwithin one or more of the traction element clusters (between thetraction elements) at the forefoot region, the midfoot region, and/orthe heel region; from of the traction element clusters; on planarregions of the traction elements (for aspects in which the material ispresent on the traction elements), and combinations thereof.

As discussed below, the water uptake capacity of the material (includinga side or surface of an outsole formed of the material) canalternatively be measured in a simulated environment, such as using thematerial co-extruded with a backing substrate. The backing substrate canbe produced from any suitable material that is compatible with thematerial, such as a material used to form an outsole backing plate. Assuch, suitable water uptake capacities at 24 hours for the material asco-extruded with a backing substrate, as characterized by the WaterUptake Capacity Test with the Co-extruded Film Sampling Procedure,include those discussed above for the Water Uptake Capacity Test withthe Footwear Sampling Procedure.

Additionally, it has been found that when the material is secured toanother surface, such as being thermally or adhesively bonded to anoutsole substrate (e.g., an outsole backing plate), the interfacial bondformed between the material and the outsole substrate can restrict theextent that the material can take up water and/or swell. As such, it isbelieved that the material as bonded to an outsole substrate orco-extruded backing substrate can potentially have a lower water uptakecapacity and/or a lower swell capacity compared to the same material ina neat material form, including neat film form.

As such, the water uptake capacity and the water uptake rate of thematerial can also be characterized based on the material in neat form(e.g., an isolated film that is not bonded to another material). Thematerial in neat form can have a water uptake capacity at 24 hoursgreater than 40% by weight, greater than 100% by weight, greater than300% by weight, or greater than 1000% by weight, as characterized by theWater Uptake Capacity Test with the Neat Film Sampling Procedure or theNeat Material Sampling Procedure. The material in neat form can alsohave a water uptake capacity at 24 hours less than 900% by weight, lessthan 800% by weight, less than 700% by weight, less than 600% by weight,or less than 500% by weight.

In particular aspects, the material in neat form has a water uptakecapacity at 24 hours ranging from 40% by weight to 900% by weight, from150% by weight to 700% by weight, from 200% by weight to 600% by weight,or from 300% by weight to 500% by weight.

The material (including a side or surface of an outsole formed of thematerial) can also have a water uptake rate greater than 20grams/(meter²-minutes^(1/2)), as characterized by the Water Uptake RateTest with the Footwear Sampling Procedure. As discussed above, in someaspects, the outsole (e.g., the material 116) can take up water betweenthe compressive cycles of foot strikes, which is believed to at leastpartially replenish the material between the foot strikes.

As such, in further aspects, the material (including a side or surfaceof an outsole formed of the material) has a water uptake rate greaterthan 20 grams/(meter²-minutes^(1/2)), greater than 100grams/(meter²-minutes^(1/2)), greater than 200grams/(meter²-minutes^(1/2)), greater than 400grams/(meter²-minutes^(1/2)), or greater than 600grams/(meter²-minutes^(1/2)). In particular aspects, the outsole has awater uptake rate ranging from 1 to 1,500 grams/(meter²-minutes^(1/2)),20 to 1,300 grams/(meter²-minutes^(1/2)), from 30 to 1,200grams/(meter²-minutes^(1/2)) from 30 to 800grams/(meter²-minutes^(1/2)), from 100 to 800grams/(meter²-minutes^(1/2)) from 100 to 600grams/(meter²-minutes^(1/2)), from 150 to 450grams/(meter²-minutes^(1/2)), from 200 to 1,000grams/(meter²-minutes^(1/2)), from 400 to 1,000grams/(meter²-minutes^(1/2)), or from 600 to 900grams/(meter²-minutes^(1/2)).

Suitable water uptake rates for the material as secured to a co-extrudedbacking substrate, as characterized by the Water Uptake Rate Test withthe Co-extruded Film Sampling Procedure, and as provided in neat form,as characterized by the Water Uptake Rate Test with the Neat FilmSampling Procedure, each include those discussed above for the WaterUptake Rate Test with the Footwear Sampling Procedure.

In certain aspects, the material (including a side or surface of anoutsole formed of the material) can also swell, increasing thematerial's thickness and/or volume, due to water uptake. This swellingof the material can be a convenient indicator showing that the materialis taking up water, and can assist in rendering the material compliant.In some aspects, the outsole has an increase in material thickness (orswell thickness increase) at 1 hour of greater than 20% or greater than50%, for example ranging from 30% to 350%, from 50% to 400%, from 50% to300%, from 100% to 300%, from 100% to 200%, or from 150% to 250%, ascharacterized by the Swelling Capacity Test with the Footwear SamplingProcedure. In further aspects, the outsole has an increase in materialthickness at 24 hours ranging from 45% to 400%, from 100% to 350%, orfrom 150% to 300%.

Additionally, the material (including a side or surface of an outsoleformed of the material) can have an increase in material volume (orvolumetric swell increase) at 1 hour of greater than 50%, for exampleranging from 10% to 130%, from 30% to 100%, or from 50% to 90%.Moreover, the outsole can have an increase in material volume at 24hours ranging from 25% to 200%, from 50% to 150%, or from 75% to 100%.

For co-extruded film simulations, suitable increases in materialthickness and volume at 1 hour and 24 hours for the material as securedto a co-extruded backing substrate, as characterized by the SwellingCapacity Test with the Co-extruded Film Sampling Procedure, includethose discussed above for the Swelling Capacity Test with the FootwearSampling Procedure.

The material in neat form can have an increase in material thickness at1 hour ranging from 35% to 400%, from 50% to 300%, or from 100% to 200%,as characterized by the Swelling Capacity Test with the Neat FilmSampling Procedure. In some further aspects, the material in neat formcan have an increase in material thickness at 24 hours ranging 45% to500%, from 100% to 400%, or from 150% to 300%. Correspondingly, thematerial in neat form can have an increase in material volume at 1 hourranging from 50% to 500%, from 75% to 400%, or from 100% to 300%.

As also discussed above, in some aspects, the surface of the materialforms a side or surface of the outsole, wherein the side or surface hashydrophilic properties. The hydrophilic properties of the material'ssurface can be characterized by determining the static sessile dropcontact angle of the material's surface. Accordingly, in some examples,the material's surface in a dry state has a static sessile drop contactangle (or dry-state contact angle) of less than 105°, or less than 95°,less than 85°, as characterized by the Contact Angle Test. The ContactAngle Test can be conducted on a sample obtained in accordance with theFootwear Sampling Procedure, the Co-Extruded Film Sampling Procedure, orthe Neat Film Sampling Procedure. In some further examples, the materialin a dry state has a static sessile drop contact angle ranging from 60°to 100°, from 70° to 100°, or from 65° to 95°.

In other examples, the material's surface in a wet state has a staticsessile drop contact angle (or wet-state contact angle) of less than90°, less than 80°, less than 70°, or less than 60°. In some furtherexamples, the surface in a wet state has a static sessile drop contactangle ranging from 45° to 75°. In some cases, the dry-state staticsessile drop contact angle of the surface is greater than the wet-statestatic sessile drop contact angle of the surface by at least 10°, atleast 15°, or at least 20°, for example from 10° to 40°, from 10° to30°, or from 10° to 20°.

The surface of the material, including the surface of an outsole canalso exhibit a low coefficient of friction when the material is wet.Examples of suitable coefficients of friction for the material in a drystate (or dry-state coefficient of friction) are less than 1.5, forinstance ranging from 0.3 to 1.3, or from 0.3 to 0.7, as characterizedby the Coefficient of Friction Test. The Coefficient of Friction Testcan be conducted on a sample obtained in accordance with the FootwearSampling Procedure, the Co-Extruded Film Sampling Procedure, or the NeatFilm Sampling Procedure. Examples of suitable coefficients of frictionfor the material in a wet state (or wet-state coefficient of friction)are less than 0.8 or less than 0.6, for instance ranging from 0.05 to0.6, from 0.1 to 0.6, or from 0.3 to 0.5. Furthermore, the material canexhibit a reduction in its coefficient of friction from its dry state toits wet state, such as a reduction ranging from 15% to 90%, or from 50%to 80%. In some cases, the dry-state coefficient of friction is greaterthan the wet-state coefficient of friction for the material, for examplebeing higher by a value of at least 0.3 or 0.5, such as 0.3 to 1.2 or0.5 to 1.

Furthermore, the compliance of the material, including an outsolecomprising the material, can be characterized by based on the material'sstorage modulus in the dry state (when equilibrated at 0% relativehumidity (RH)), and in a partially wet state (e.g., when equilibrated at50% RHor at 90% RH), and by reductions in its storage modulus betweenthe dry and wet states. In particular, the material can have a reductionin storage modulus (ΔE′) from the dry state relative to the wet state. Areduction in storage modulus as the water concentration in the materialincreases corresponds to an increase in compliance, because less stressis required for a given strain/deformation.

In some aspects, the material exhibits a reduction in the storagemodulus from its dry state to its wet state (50% RH) of more than 20%,more than 40%, more than 60%, more than 75%, more than 90%, or more than99%, relative to the storage modulus in the dry state, and ascharacterized by the Storage Modulus Test with the Neat Film SamplingProcess. In some further aspects, the dry-state storage modulus of thematerial is greater than its wet-state (50% RH) storage modulus by morethan 25 megaPascals (MPa), by more than 50 MPa, by more than 100 MPa, bymore than 300 MPa, or by more than 500 MPa, for example ranging from 25MPa to 800 MPa, from 50 MPa to 800 MPa, from 100 MPa to 800 MPa, from200 MPa to 800 MPa, from 400 MPa to 800 MPa, from 25 MPa to 200 MPa,from 25 MPa to 100 MPa, or from 50 MPa to 200 MPa. Additionally, thedry-state storage modulus can range from 40 MPa to 800 MPa, from 100 MPato 600 MPa, or from 200 MPa to 400 MPa, as characterized by the StorageModulus Test. Additionally, the wet-state storage modulus can range from0.003 MPa to 100 MPa, from 1 MPa to 60 MPa, or from 20 MPa to 40 MPa.

In other aspects, the material exhibits a reduction in the storagemodulus from its dry state to its wet state (90% RH) of more than 20%,more than 40%, more than 60%, more than 75%, more than 90%, or more than99%, relative to the storage modulus in the dry state, and ascharacterized by the Storage Modulus Test with the Neat Film SamplingProcess. In further aspects, the dry-state storage modulus of thematerial is greater than its wet-state (90% RH) storage modulus by morethan 25 megaPascals (MPa), by more than 50 MPa, by more than 100 MPa, bymore than 300 MPa, or by more than 500 MPa, for example ranging from 25MPa to 800 MPa, from 50 MPa to 800 MPa, from 100 MPa to 800 MPa, from200 MPa to 800 MPa, from 400 MPa to 800 MPa, from 25 MPa to 200 MPa,from 25 MPa to 100 MPa, or from 50 MPa to 200 MPa. Additionally, thedry-state storage modulus can range from 40 MPa to 800 MPa, from 100 MPato 600 MPa, or from 200 MPa to 400 MPa, as characterized by the StorageModulus Test. Additionally, the wet-state storage modulus can range from0.003 MPa to 100 MPa, from 1 MPa to 60 MPa, or from 20 MPa to 40 MPa.

In addition to a reduction in storage modulus, the material can alsoexhibit a reduction in its glass transition temperature from the drystate (when equilibrated at 0% relative humidity (RH) to the wet state(when equilibrated at 90% RH). While not wishing to be bound by theory,it is believed that the water taken up by the material plasticizes thematerial, which reduces its storage modulus and its glass transitiontemperature, rendering the material more compliant (e.g., compressible,expandable, and stretchable).

In some aspects, the material can exhibit a reduction in glasstransition temperature (ΔT_(g)) from its dry-state (0% RH) glasstransition temperature to its wet-state glass transition (90% RH)temperature of more than a 5° C. difference, more than a 6° C.difference, more than a 10° C. difference, or more than a 15° C.difference, as characterized by the Glass Transition Temperature Testwith the Neat Film Sampling Process or the Neat Material SamplingProcess. For instance, the reduction in glass transition temperature(ΔT_(g)) can range from more than a 5° C. difference to a 40° C.difference, from more than a 6° C. difference to a 50° C. difference,form more than a 10° C. difference to a 30° C. difference, from morethan a 30° C. difference to a 45° C. difference, or from a 15° C.difference to a 20° C. difference. The material can also exhibit a dryglass transition temperature ranging from −40° C. to −80° C., or from−40° C. to −60° C.

Alternatively (or additionally), the reduction in glass transitiontemperature (ΔT_(g)) can range from a 5° C. difference to a 40° C.difference, form a 10° C. difference to a 30° C. difference, or from a15° C. difference to a 20° C. difference. The material can also exhibita dry glass transition temperature ranging from −40° C. to −80° C., orfrom −40° C. to −60° C.

In further aspects, the material can exhibit a soil shedding abilitywith a relative impact energy ranging from 0 to 0.9, from 0.2 to 0.7, orfrom 0.4 to 0.5, as characterized by the Impact Energy Test with theFootwear Sampling Procedure, the Co-extruded Film Sampling Procedure,the Neat Film Sampling Procedure, or the Neat Material SamplingProcedure. Moreover, the material (e.g., the material 116) is preferablydurable enough, and has a sufficient bond to the outsole backing plate,for use over extended durations in game play. For instance, it has beenfound that the material of the present disclosure can, in some aspects,continue to perform without significant visual abrasion or delaminationfor more than 80 or 100 hours, as discussed above.

In some particular aspects, the material compositionally includes ahydrophilic polymer and optionally one or more additives. In furtheraspects, the material compositionally includes a polymeric network(e.g., a hydrophilic polymeric network) and optionally one or moreadditives. The polymeric network is preferably a plurality ofcrosslinked (or crosslinkable) polymer chains, where the polymer chainscan be homopolymers, copolymers, or a combination of both homopolymersand copolymers. When crosslinked, the network can be either physicallyor covalently or both physically and covalently crosslinked. In someexamples, the polymeric network can function as a hydrogel. As usedherein, the term “hydrogel” refers to a composition that is capable oftaking up at least 10% by weight in water, based on a dry weight of thecomposition. The polymeric network can constitute more than 50% byweight of the entire material for the outsole, or more than 75% byweight, or more 85% by weight, or more than 95% by weight. In someaspects, the material of the outsole consists essentially of thepolymeric network and optionally one or more colorants.

For a physical crosslink, a copolymer chain can form entangled regionsand/or crystalline regions through non-covalent bonding interactions,such as, for example, an ionic bond, a polar bond, and/or a hydrogenbond. In particular aspects, the crystalline regions create the physicalcrosslink between the copolymer chains. The crystalline regions caninclude hard segments, as described below.

In some aspects, the polymeric network can exhibit sol-gelreversibility, allowing it to function as a thermoplastic polymer, whichcan be advantageous for manufacturing and recyclability. As such, insome aspects, the polymeric network of the material includes aphysically crosslinked polymeric network to function as a thermoplasticmaterial.

The physically crosslinked polymeric networks can be characterized byhard segments and soft segments, which can exist as phase separatedregions within the polymeric network while the polymeric network is in asolid (non-molten) state. The hard segments can form portions of thepolymer chain backbones, and can exhibit high polarities, allowing thehard segments of multiple polymer chains to aggregate together, orinteract with each other, to form semi-crystalline regions of thepolymeric network.

A “semi-crystalline” or “crystalline” region has an ordered molecularstructure with sharp melt points, which remains solid until a givenquantity of heat is absorbed and then rapidly changes into a lowviscosity liquid. A “pseudo-crystalline” region has properties of acrystal, but does not exhibit a true crystalline diffraction pattern.For ease of reference, the term “crystalline region” will be used hereinto collectively refer to a crystalline region, a semi-crystallineregion, and a pseudo-crystalline region of a polymeric network.

In comparison, the soft segments can be longer, more flexible,hydrophilic regions of the polymeric network that allow the polymernetwork to expand and swell under the pressure of taken up water. Thesoft segments can constitute amorphous hydrophilic regions of thepolymeric network. The soft segments, or amorphous regions, can alsoform portions of the backbones of the polymer chains along with the hardsegments. Additionally, one or more portions of the soft segments, oramorphous regions, can be grafted or otherwise extend as pendant chainsthat extend from the backbones at the soft segments. The soft segments,or amorphous regions, can be covalently bonded to the hard segments, orcrystalline regions (e.g., through carbamate linkages). For example, aplurality of amorphous hydrophilic regions can be covalently bonded tothe crystalline regions of the hard segments.

Thus, in various aspects, the polymeric network comprises a crosslinkedpolymeric network which includes a plurality of copolymer chains whereinat least a portion of the copolymer chains each comprise a hard segmentphysically crosslinked to other hard segments of the copolymer chainsand a soft segment covalently bonded to the hard segment, such asthrough a carbamate group or an ester group. In some cases, thepolymeric network includes a plurality of copolymer chains wherein atleast a portion of the copolymer chains each comprise a first chainsegment physically crosslinked to at least one other copolymer chain ofthe plurality of copolymer chains and a hydrophilic segment (e.g., apolyether chain segment) covalently bonded to the first chain segment,such as through a carbamate group or an ester group.

In various aspects, the polymeric network includes a plurality ofcopolymer chains, wherein at least a portion of the copolymer chainseach include a first segment forming at least a crystalline region withother hard segments of the copolymer chains; and a second segment, suchas a soft segment (e.g., a segment having polyether chains or one ormore ether groups) covalently bonded to the first segment, where thesoft segment forms amorphous regions of the polymeric network. In somecases, the polymeric network includes a plurality of copolymer chains,where at least a portion of the copolymer chains have hydrophilicsegments.

The soft segments, or amorphous regions, of the copolymer chains canconstitute a substantial portion of the polymeric network, allowingtheir hydrophilic segments or groups to attract water molecules. In someaspects, the soft segments, or amorphous regions, are present in thecopolymer chains in a ratio (relative to the hard segments, orcrystalline regions) that is at least or greater than 20:1 by weight,that ranges from 20:1 to 110:1 by weight, or from 40:1 to 110:1 byweight, or from 40:1 to 80:1 by weight, or from 60:1 to 80:1.

For a covalent crosslink, one polymer chain is linked to one or moreadditional polymer chains with one or more covalent bonds, typicallywith a linking segment or chain. Covalently crosslinked polymericnetworks (e.g., thermoset and photocured polymer networks) can beprepared by covalently linking the polymer chains together using one ormore multi-functional compounds, such as, for example, a molecule havingat least two ethylenically-unsaturated groups, at least two oxiranegroups (e.g., diepoxides), or combinations thereof (e.g., glycidylmethacrylate); and can also include any suitable intermediate chainsegment, such as C₁₋₃₀, C₂₋₂₀, or C₂₋₁₀ hydrocarbon, polyether, orpolyester chain segments.

The multi-functional compounds can include at least three functionalgroups selected from the group consisting of isocyanidyl, hydroxyl,amino, sulfhydryl, carboxyl or derivatives thereof, and combinationsthereof. In some aspects, such as when the polymer network includespolyurethane, the multi-functional compound can be a polyol having threeor more hydroxyl groups (e.g., glycerol, trimethylolpropane,1,2,6-hexanetriol, 1,2,4-butanetriol, trimethylolethane) or apolyisocyanate having three or more isocyanate groups. In some cases,such as when the polymer network includes polyamide, themulti-functional compound can include, for example, carboxylic acids oractivated forms thereof having three or more carboxyl groups (oractivated forms thereof, polyamines having three or more amino groups,and polyols having three or more hydroxyl groups (e.g., glycerol,trimethylolpropane, 1,2,6-hexanetriol, 1,2,4-butanetriol, andtrimethylolethane). In various cases, such as when the polymer networkincludes polyolefin, the multi-functional compound can be a compoundhaving two ethylenically-unsaturated groups.

When the polymeric network of the material is crosslinked, it has beenfound that the crosslinking density of the crosslinked polymeric networkcan impact the structural integrity and water uptake capacities of thematerial (e.g., the material 116). If the crosslinking density is toohigh, the resulting material can be stiff and less compliant, which canreduce its water uptake and swelling capacity. On the other hand, if thecrosslinking density is too low, then the resulting material can loseits structural integrity when saturated. As such, the polymericnetwork(s) of the material preferably have a balanced crosslinkingdensity such that the material retains its structural integrity, yet isalso sufficiently compliant when partially or fully saturated withwater.

The polymeric network of the material (e.g., the material 116) caninclude any suitable polymer chains that provide the functionalproperties disclosed herein (e.g., water uptake, swelling, and moregenerally, preventing soil accumulation). For example, the polymericnetwork can be a polymeric network comprising or consisting essentiallyof one or more polymer chains such as one or more polyurethanes, one ormore polyamides, one or more polyolefins, and combinations thereof(e.g., a polymeric network based on polyurethane(s) and polyamide(s)).The polymeric network can comprise or consist essentially of one or morepolysiloxane chains (i.e., the polymeric network can comprise or consistessentially of a silicone-containing polymer network, such as a siliconehydrogel). The polymeric network can comprise or consist essentially ofone or more ionomeric polymer chains (i.e., the network can comprise orconsist essentially of an ionomeric polymers). In these aspects, thepolymeric network can include a plurality of copolymer chains wherein atleast a portion of the copolymer chains each include a polyurethanesegment, a polyamide segment, a polyolefin segment, a polysiloxanesegment, an ionomer segment, and combinations thereof. The segments cancomprise one or more polyurethanes, one or more polyamides, one or morepolyolefins, and combinations thereof.

In some aspects, the polymeric network is a polymeric network with oneor more polyurethane copolymer chains (i.e., a plurality of polyurethanechains), referred to as a “polyurethane polymeric network”. Thepolyurethane polymeric network can be physically and/or covalentlycrosslinked. The polyurethane polymeric network can be produced bypolymerizing one or more isocyanates with one or more polyols to producecopolymer chains having carbamate linkages (—N(CO)O—) as illustratedbelow in Formula 1, where the isocyanate(s) each preferably include twoor more isocyanate (—NCO) groups per molecule, such as 2, 3, or 4isocyanate groups per molecule (although, single-functional isocyanatescan also be optionally included, e.g., as chain terminating units).

In these aspects, each R₁ independently is an aliphatic or aromaticsegment, and each R₂ is a hydrophilic segment.

Unless otherwise indicated, any of the functional groups or chemicalcompounds described herein can be substituted or unsubstituted. A“substituted” group or chemical compound, such as an alkyl, alkenyl,alkynyl, cycloalkyl, cycloalkenyl, aryl, heteroaryl, alkoxyl, ester,ether, or carboxylic ester refers to an alkyl, alkenyl, alkynyl,cycloalkyl, cycloalkenyl, aryl, heteroaryl, alkoxyl, ester, ether, orcarboxylic ester group, has at least one hydrogen radical that issubstituted with a non-hydrogen radical (i.e., a substitutent). Examplesof non-hydrogen radicals (or substituents) include, but are not limitedto, alkyl, cycloalkyl, alkenyl, cycloalkenyl, alkynyl, ether, aryl,heteroaryl, heterocycloalkyl, hydroxyl, oxy (or oxo), alkoxyl, ester,thioester, acyl, carboxyl, cyano, nitro, amino, amido, sulfur, and halo.When a substituted alkyl group includes more than one non-hydrogenradical, the substituents can be bound to the same carbon or two or moredifferent carbon atoms.

Additionally, the isocyanates can also be chain extended with one ormore chain extenders to bridge two or more isocyanates. This can producepolyurethane copolymer chains as illustrated below in Formula 2, whereinR₃ includes the chain extender.

Each segment R₁, or the first segment, in Formulas 1 and 2 canindependently include a linear or branched C₃₋₃₀ segment, based on theparticular isocyanate(s) used, and can be aliphatic, aromatic, orinclude a combination of aliphatic portions(s) and aromatic portion(s).The term “aliphatic” refers to a saturated or unsaturated organicmolecule that does not include a cyclically conjugated ring systemhaving delocalized pi electrons. In comparison, the term “aromatic”refers to a cyclically conjugated ring system having delocalized pielectrons, which exhibits greater stability than a hypothetical ringsystem having localized pi electrons.

In aliphatic aspects (from aliphatic isocyanate(s)), each segment R₁ caninclude a linear aliphatic group, a branched aliphatic group, acycloaliphatic group, or combinations thereof. For instance, eachsegment R₁ can include a linear or branched C₃₋₂₀ alkylene segment(e.g., C₄₋₁₅ alkylene or C₆₋₁₀ alkylene), one or more C₃₋₈ cycloalkylenesegments (e.g., cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl,cycloheptyl, or cyclooctyl), and combinations thereof.

Examples of suitable aliphatic diisocyanates for producing thepolyurethane copolymer chains include hexamethylene diisocyanate (HDI),isophorone diisocyanate (IPDI), butylene diisocyanate (BDI),bisisocyanatocyclohexylmethane (HMDI), 2,2,4-trimethylhexamethylenediisocyanate (TMDI), bisisocyanatomethylcyclohexane,bisisocyanatomethyltricyclodecane, norbornane diisocyanate (NDI),cyclohexane diisocyanate (CHDI), 4,4′-dicyclohexylmethane diisocyanate(H12MDI), diisocyanatododecane, lysine diisocyanate, and combinationsthereof.

In aromatic aspects (from aromatic isocyanate(s)), each segment R₁ caninclude one or more aromatic groups, such as phenyl, naphthyl,tetrahydronaphthyl, phenanthrenyl, biphenylenyl, indanyl, indenyl,anthracenyl, and fluorenyl. Unless otherwise indicated, an aromaticgroup can be an unsubstituted aromatic group or a substituted aromaticgroup, and can also include heteroaromatic groups. “Heteroaromatic”refers to monocyclic or polycyclic (e.g., fused bicyclic and fusedtricyclic) aromatic ring systems, where one to four ring atoms areselected from oxygen, nitrogen, or sulfur, and the remaining ring atomsare carbon, and where the ring system is joined to the remainder of themolecule by any of the ring atoms. Examples of suitable heteroarylgroups include pyridyl, pyrazinyl, pyrimidinyl, pyrrolyl, pyrazolyl,imidazolyl, thiazolyl, tetrazolyl, oxazolyl, isooxazolyl, thiadiazolyl,oxadiazolyl, furanyl, quinolinyl, isoquinolinyl, benzoxazolyl,benzimidazolyl, and benzothiazolyl.

Examples of suitable aromatic diisocyanates for producing thepolyurethane copolymer chains include toluene diisocyanate (TDI), TDIadducts with trimethyloylpropane (TMP), methylene diphenyl diisocyanate(MDI), xylene diisocyanate (XDI), tetramethylxylylene diisocyanate(TMXDI), hydrogenated xylene diisocyanate (HXDI), naphthalene1,5-diisocyanate (NDI), 1,5-tetrahydronaphthalene diisocyanate,para-phenylene diisocyanate (PPDI),3,3′-dimethyldiphenyl-4,4′-diisocyanate (DDDI), 4,4′-dibenzyldiisocyanate (DBDI), 4-chloro-1,3-phenylene diisocyanate, andcombinations thereof. In some aspects, the copolymer chains aresubstantially free of aromatic groups.

In some preferred aspects, the polyurethane copolymer chains areproduced from diisocynates including HMDI, TDI, MDI, H₁₂ aliphatics, andcombinations thereof.

Examples of suitable triisocyanates for producing the polyurethanecopolymer chains include TDI, HDI, and IPDI adducts withtrimethyloylpropane (TMP), uretdiones (i.e., dimerized isocyanates),polymeric MDI, and combinations thereof.

Segment R₃ in Formula 2 can include a linear or branched C₂₋C₁₀ segment,based on the particular chain extender polyol used, and can be, forexample, aliphatic, aromatic, or polyether. Examples of suitable chainextender polyols for producing the polyurethane copolymer chains includeethylene glycol, lower oligomers of ethylene glycol (e.g., diethyleneglycol, triethylene glycol, and tetraethylene glycol), 1,2-propyleneglycol, 1,3-propylene glycol, lower oligomers of propylene glycol (e.g.,dipropylene glycol, tripropylene glycol, and tetrapropylene glycol),1,4-butylene glycol, 2,3-butylene glycol, 1,6-hexanediol,1,8-octanediol, neopentyl glycol, 1,4-cyclohexanedimethanol,2-ethyl-1,6-hexanediol, 1-methyl-1,3-propanediol,2-methyl-1,3-propanediol, dihydroxyalkylated aromatic compounds (e.g.,bis(2-hydroxyethyl) ethers of hydroquinone and resorcinol,xylene-α,α-diols, bis(2-hydroxyethyl) ethers of xylene-α,α-diols, andcombinations thereof.

Segment R₂ in Formula 1 and 2 can include polyether, polyester,polycarbonate, an aliphatic group, or an aromatic group, wherein thealiphatic group or aromatic group is substituted with one or morependant hydrophilic groups selected from the group consisting ofhydroxyl, polyether, polyester, polylactone (e.g., polyvinylpyrrolidone(PVP)), amino, carboxylate, sulfonate, phosphate, ammonium (e.g.,tertiary and quaternary ammonium), zwitterion (e.g., a betaine, such aspoly(carboxybetaine (pCB) and ammonium phosphonates such asphosphatidylcholine), and combinations thereof. Therefore, thehydrophilic segment of R₂ can form portions of the polymer backbone, orbe grafted to the polymer backbone as a pendant group. In some aspects,the pendant hydrophilic group or segment is bonded to the aliphaticgroup or aromatic group through a linker. Each segment R₂ can be presentin an amount of 5% to 85% by weight, from 5% to 70% by weight, or from10% to 50% by weight, based on the total weight of the reactantmonomers.

In some aspects, at least one R₂ segment includes a polyether segment(i.e., a segment having one or more ether groups). Suitable polyethersinclude, but are not limited to polyethylene oxide (PEO), polypropyleneoxide (PPO), polytetrahydrofuran (PTHF), polytetramethylene oxide(PTMO), and combinations thereof. The term “alkyl” as used herein refersto straight chained and branched saturated hydrocarbon groups containingone to thirty carbon atoms, for example, one to twenty carbon atoms, orone to ten carbon atoms. The term C_(n) means the alkyl group has “n”carbon atoms. For example, C₄ alkyl refers to an alkyl group that has 4carbon atoms. C₁₋₇ alkyl refers to an alkyl group having a number ofcarbon atoms encompassing the entire range (i.e., 1 to 7 carbon atoms),as well as all subgroups (e.g., 1-6, 2-7, 1-5, 3-6, 1, 2, 3, 4, 5, 6,and 7 carbon atoms). Non-limiting examples of alkyl groups include,methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl (2-methylpropyl),t-butyl (1,1-dimethylethyl), 3,3-dimethylpentyl, and 2-ethylhexyl.Unless otherwise indicated, an alkyl group can be an unsubstituted alkylgroup or a substituted alkyl group.

In some cases, at least one R₂ segment includes a polyester segment. Thepolyester can be derived from the polyesterification of one or moredihydric alcohols (e.g., ethylene glycol, 1,3-propylene glycol,1,2-propylene glycol, 1,4-butanediol, 1,3-butanediol,2-methylpentanediol-1,5, diethylene glycol, 1,5-pentanediol,1,5-hexanediol, 1,2-dodecanediol, cyclohexanedimethanol, andcombinations thereof) with one or more dicarboxylic acids (e.g., adipicacid, succinic acid, sebacic acid, suberic acid, methyladipic acid,glutaric acid, pimelic acid, azelaic acid, thiodipropionic acid andcitraconic acid and combinations thereof). The polyester also can bederived from polycarbonate prepolymers, such as poly(hexamethylenecarbonate) glycol, poly(propylene carbonate) glycol, poly(tetramethylenecarbonate)glycol, and poly(nonanemethylene carbonate) glycol. Suitablepolyesters can include, for example, polyethylene adipate (PEA),poly(1,4-butylene adipate), poly(tetramethylene adipate),poly(hexamethylene adipate), polycaprolactone, polyhexamethylenecarbonate, poly(propylene carbonate), poly(tetramethylene carbonate),poly(nonanemethylene carbonate), and combinations thereof.

In various cases, at least one R₂ segment includes a polycarbonatesegment. The polycarbonate can be derived from the reaction of one ormore dihydric alcohols (e.g., ethylene glycol, 1,3-propylene glycol,1,2-propylene glycol, 1,4-butanediol, 1,3-butanediol,2-methylpentanediol-1,5, diethylene glycol, 1,5-pentanediol,1,5-hexanediol, 1,2-dodecanediol, cyclohexanedimethanol, andcombinations thereof) with ethylene carbonate.

In various aspects, at least one R₂ segment includes an aliphatic groupsubstituted with one or more hydrophilic groups selected from the groupconsisting of hydroxyl, polyether, polyester, polylactone (e.g.,polyvinylpyrrolidone), amino, carboxylate, sulfonate, phosphate,ammonium (e.g., tertiary and quaternary ammonium), zwitterion (e.g., abetaine, such as poly(carboxybetaine (pCB) and ammonium phosphonatessuch as phosphatidylcholine), and combinations thereof. In some aspects,the aliphatic group is linear and can include, for example, a C₁₋₂₀alkylene chain or a C₁₋₂₀ alkenylene chain (e.g., methylene, ethylene,propylene, butylene, pentylene, hexylene, heptylene, octylene, nonylene,decylene, undecylene, dodecylene, tridecylene, ethenylene, propenylene,butenylene, pentenylene, hexenylene, heptenylene, octenylene,nonenylene, decenylene, undecenylene, dodecenylene, tridecenylene). Theterm “alkylene” refers to a bivalent hydrocarbon. The term C_(n) meansthe alkylene group has “n” carbon atoms. For example, C₁₋₆alkylenerefers to an alkylene group having, e.g., 1, 2, 3, 4, 5, or 6 carbonatoms. The term “alkenylene” refers to a bivalent hydrocarbon having atleast one double bond.

In some cases, at least one R₂ segment includes an aromatic groupsubstituted with one or more hydrophilic groups selected from the groupconsisting of hydroxyl, polyether, polyester, polylactone (e.g.,polyvinylpyrrolidone), amino, carboxylate, sulfonate, phosphate,ammonium (e.g., tertiary and quaternary ammonium), zwitterion (e.g., abetaine, such as poly(carboxybetaine (pCB) and ammonium phosphonatessuch as phosphatidylcholine), and combinations thereof. Suitablearomatic groups include, but are not limited to, phenyl, naphthyl,tetrahydronaphthyl, phenanthrenyl, biphenylenyl, indanyl, indenyl,anthracenyl, fluorenylpyridyl, pyrazinyl, pyrimidinyl, pyrrolyl,pyrazolyl, imidazolyl, thiazolyl, tetrazolyl, oxazolyl, isooxazolyl,thiadiazolyl, oxadiazolyl, furanyl, quinolinyl, isoquinolinyl,benzoxazolyl, benzimidazolyl, and benzothiazolyl.

The aliphatic and aromatic groups are substituted with an appropriatenumber of pendant hydrophilic and/or charged groups so as to provide theresulting polymeric network with the properties described herein. Insome aspects, the pendant hydrophilic group is one or more (e.g., 2, 3,4, 5, 6, 7, 8, 9, 10 or more) hydroxyl groups. In various aspects, thependant hydrophilic group is one or more (e.g., 2, 3, 4, 5, 6, 7, 8, 9,10 or more) amino groups. In some cases, the pendant hydrophilic groupis one or more (e.g., 2, 3, 4, 5, 6, 7, 8, 9, 10 or more) carboxylategroups. For example, the aliphatic group can include polyacrylic acid.In some cases, the pendant hydrophilic group is one or more (e.g., 2, 3,4, 5, 6, 7, 8, 9, 10 or more) sulfonate groups. In some cases, thependant hydrophilic group is one or more (e.g., 2, 3, 4, 5, 6, 7, 8, 9,10 or more) phosphate groups. In some aspects, the pendant hydrophilicgroup is one or more ammonium groups (e.g., tertiary and/or quaternaryammonium). In other aspects, the pendant hydrophilic group is one ormore zwitterions (e.g., a betaine, such as poly(carboxybetaine (pCB) andammonium phosphonates such as phosphatidylcholine).

In some aspects, the R₂ segment includes charged groups that are capableof binding to a counterion to ionically crosslink the polymer thepolymer network and form ionomers. In these aspects, for example, R₂ isan aliphatic or aromatic group having pendant amino, carboxylate,sulfonate, phosphate, ammonium, zwitterionic groups, or combinationsthereof. For example, R₂ can be an aliphatic or aromatic group havingone or more pendant carboxylate group.

In various cases, the pendant hydrophilic group is at least onepolyether, such as two polyethers. In other cases, the pendanthydrophilic group is at least one polyester. In various cases, thependant hydrophilic group is polylactone (e.g., polyvinylpyrrolidone).Each carbon atom of the pendant hydrophilic group can optionally besubstituted with, e.g., C₁₋₆ alkyl. In some of these aspects, thealiphatic and aromatic groups can be graft polymers, wherein the pendantgroups are homopolymers (e.g., polyethers, polyesters,polyvinylpyrrolidone).

In some preferred aspects, the pendant hydrophilic group is a polyether(e.g., polyethylene oxide and polyethylene glycol),polyvinylpyrrolidone, polyacrylic acid, or combinations thereof.

The pendant hydrophilic group can be bonded to the aliphatic group oraromatic group through a linker. The linker can be any bifunctionalsmall molecule (e.g., C₁₋₂₀) capable of linking the pendant hydrophilicgroup to the aliphatic or aromatic group. For example, the linker caninclude a diisocyanate, as previously described herein, which whenlinked to the pendant hydrophilic group and to the aliphatic or aromaticgroup forms a carbamate bond. In some aspects, the linker can be4,4′-diphenylmethane diisocyanate (MDI), as shown below.

In some exemplary aspects, the pendant hydrophilic group is polyethyleneoxide and the linking group is MDI, as shown below.

In some cases, the pendant hydrophilic group is functionalized to enableit to bond to the aliphatic or aromatic group, optionally through thelinker. In various aspects, for example, when the pendant hydrophilicgroup includes an alkene group, which can undergo a Michael additionwith a sulfhydryl-containing bifunctional molecule (i.e., a moleculehaving a second reactive group, such as a hydroxyl group or aminogroup), to result in a hydrophilic group that can react with the polymerbackbone, optionally through the linker, using the second reactivegroup. For example, when the pendant hydrophilic group ispolyvinylpyrrolidone, it can react with the sulfhydryl group onmercaptoethanol to result in hydroxyl-functionalizedpolyvinylpyrrolidone, as shown below.

In some of the aspects disclosed herein, at least one R₂ segment ispolytetramethylene oxide. In other exemplary aspects, at least one R₂segment can be an aliphatic polyol functionalized with polyethyleneoxide or polyvinylpyrrolidone, such as the polyols described in E.P.Patent No. 2 462 908. For example, the R₂ segment can be derived fromthe reaction product of a polyol (e.g., pentaerythritol or2,2,3-trihydroxypropanol) and either MDI-derivatized methoxypolyethyleneglycol (to obtain compounds as shown in Formulas 6 or 7) or withMDI-derivatized polyvinylpyrrolidone (to obtain compounds as shown inFormulas 8 or 9) that had been previously been reacted withmercaptoethanol, as shown below,

In various cases, at least one R₂ is a polysiloxane. In these cases, R₂can be derived from a silicone monomer of Formula 10, such as a siliconemonomer disclosed in U.S. Pat. No. 5,969,076:

wherein:

a is 1 to 10 or larger (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10);

each R⁴ independently is hydrogen, C₁₋₁₈ alkyl, C₂₋₁₈ alkenyl, aryl, orpolyether; and

each R⁵ independently is C₁₋₁₀alkylene, polyether, or polyurethane.

In some aspects, each R⁴ independently is H, C₁₋₁₀ alkyl, C₂₋₁₀alkenyl,C₁₋₆aryl, polyethylene, polypropylene, or polybutylene. For example,each R⁴ can independently be selected from the group consisting ofmethyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, s-butyl, t-butyl,ethenyl, propenyl, phenyl, and polyethylene.

In various aspects, each R⁵ independently is C₁₋₁₀alkylene (e.g.,methylene, ethylene, propylene, butylene, pentylene, hexylene,heptylene, octylene, nonylene, or decylene). In other cases, each R⁵ ispolyether (e.g., polyethylene, polypropylene, or polybutylene). Invarious cases, each R⁵ is polyurethane.

In some aspects, the polymeric network includes a crosslinked polymericnetwork that includes copolymer chains that are derivatives ofpolyurethane. This crosslinked polymeric network can be produced bypolymerizing one or more isocyanates with one or more polyaminocompounds, polysulfhydryl compounds, or combinations thereof, as shownin Formulas 11 and 12, below:

wherein the variables are as described above. Additionally, theisocyanates can also be chain extended with one or more polyamino orpolythiol chain extenders to bridge two or more isocyanates, such aspreviously described for the polyurethanes of Formula 2.

In some aspects, the polyurethane polymeric network is composed of MDI,PTMO, and 1,4-butylene glycol, as described in U.S. Pat. No. 4,523,005.

In some aspects, the polyurethane polymeric network is physicallycrosslinked through e.g., nonpolar or polar interactions between theurethane or carbamate groups on the polymers (the hard segments), and isa thermoplastic polyurethane (TPU), or specifically, what may bereferred to as a hydrophilic thermoplastic polyurethane. In theseaspects, component R₁ in Formula 1, and components R₁ and R₃ in Formula2, forms the portion of the polymer often referred to as the “hardsegment”, and component R₂ forms the portion of the polymer oftenreferred to as the “soft segment”. In these aspects, the soft segmentcan be covalently bonded to the hard segment.

Commercially available thermoplastic polyurethane hydrogels suitable forthe present use include, but are not limited to those under thetradename “TECOPHILIC”, such as TG-500, TG-2000, SP-80A-150, SP-93A-100,SP-60D-60 (Lubrizol, Countryside, Ill.), “ESTANE” (e.g., ALR G 500;Lubrizol, Countryside, Ill.).

In various aspects, the polyurethane polymeric network is covalentlycrosslinked, as previously described herein.

In some aspects, the polyamide segment of the polyamide polymericnetwork comprises or consists essentially of a polyamide. The polyamidepolymeric network can be formed from the polycondensation of a polyamideprepolymer with a hydrophilic prepolymer to form a block copolyamide.

In some aspects, the polyamide segment of the polyamide polymer chainsof the polymeric network can be derived from the condensation ofpolyamide prepolymers, such as lactams, amino acids, and/or diaminocompounds with dicarboxylic acids, or activated forms thereof. Theresulting polyamide segments include amide linkages (—(CO)NH—). The term“amino acid” refers to a molecule having at least one amino group and atleast one carboxyl group. Each polyamide segment of the polyamidepolymer chain can be the same or different.

In some aspects, the polyamide segment is derived from thepolycondensation of lactams and/or amino acids, and includes an amidesegment having a structure shown in Formula 13, below, wherein R₆ is thesegment of the block copolymer derived from the lactam or amino acid,and R₂ is the segment derived from a hydrophilic prepolymer:

In some aspects, R₆ is derived from a lactam. In some cases, R₆ isderived from a C₃₋₂₀ lactam, or a C₄₋₁₅ lactam, or a C₆₋₁₂ lactam. Forexample, R₆ can be derived from caprolactam or laurolactam. In somecases, R₆′ is derived from one or more amino acids. In various cases, R₆is derived from a C₄₋₂₅ amino acid, or a C₅₋₂₀ amino acid, or a C₈₋₁₅amino acid. For example, R₆′ can be derived from 12-aminolauric acid or11-aminoundecanoic acid.

In some cases, Formula 13 includes a polyamide-polyether block copolymersegment, as shown below:

wherein m is 3-20, and n is 1-8. In some exemplary aspects, m is 4-15,or 6-12 (e.g., 6, 7, 8, 9, 10, 11, or 12), and n is 1, 2, or 3. Forexample, m can be 11 or 12, and n can be 1 or 3.

In various aspects, the polyamide segment of the polyamide polymer chainis derived from the condensation of diamino compounds with dicarboxylicacids, or activated forms thereof, and includes an amide segment havinga structure shown in Formula 15, below, wherein R₇ is the segment of theblock copolymer derived from the diamino compound, R₈ is the segmentderived from the dicarboxylic acid compound, and R₂ is the segmentderived from a hydrophilic prepolymer:

In some aspects, R₇ is derived from a diamino compound that includes analiphatic group having C₄₋₁₅ carbon atoms, or C₅₋₁₀ carbon atoms, orC₆₋₉ carbon atoms. In some aspects, the diamino compound includes anaromatic group, such as phenyl, naphthyl, xylyl, and tolyl. Suitablediamino compounds include, but are not limited to, hexamethylene diamine(HMD), tetramethylene diamine, trimethyl hexamethylene diamine (TMD),m-xylylene diamine (MXD), and 1,5-pentamine diamine. In various aspects,R₈ is derived from a dicarboxylic acid or activated form thereof,includes an aliphatic group having C₄₋₁₅ carbon atoms, or C₅₋₁₂ carbonatoms, or C₆₋₁₀ carbon atoms. In some cases, the dicarboxylic acid oractivated form thereof includes an aromatic group, such as phenyl,naphthyl, xylyl, and tolyl. Suitable carboxylic acids or activated formsthereof include, but are not limited to adipic acid, sebacic acid,terephthalic acid, and isophthalic acid. In some aspects, the copolymerchains are substantially free of aromatic groups.

In some preferred aspects, each polyamide segment is independentlyderived from a polyamide prepolymer selected from the group consistingof 12-aminolauric acid, caprolactam, hexamethylene diamine and adipicacid.

Additionally, the polyamide polymeric networks can also be chainextended with one or more polyamino, polycarboxyl (or derivativesthereof), or amino acid chain extenders, as previously described herein.In some aspects, the chain extender can include a diol, dithiol, aminoalcohol, aminoalkyl mercaptan, hydroxyalkyl mercaptan, a phosphite or abisacyllactam compound (e.g., triphenylphosphite, N,N′-terephthaloylbis-laurolactam, and diphenyl isophthalate).

Each component R₂ of Formula 13 and 15 independently is polyether,polyester, polycarbonate, an aliphatic group, or an aromatic group,wherein the aliphatic group or aromatic group is substituted with one ormore pendant hydrophilic groups, as previously described herein, whereinthe pendant group can optionally be bonded to the aliphatic or aromaticgroup through a linker, as previously described herein.

In some preferred aspects, R₂ is derived from a compound selected fromthe group consisting of polyethylene oxide (PEO), polypropylene oxide(PPO), polytetrahydrofuran (PTHF), polytetramethylene oxide (PTMO), apolyethylene oxide-functionalized aliphatic or aromatic group, apolyvinylpyrrolidone-functionalized aliphatic of aromatic group, andcombinations thereof. In various cases, R₂ is derived from a compoundselected from the group consisting of polyethylene oxide (PEO),polypropylene oxide (PPO), polytetramethylene oxide (PTMO), apolyethylene oxide-functionalized aliphatic or aromatic group, andcombinations thereof. For example, R₂ can be derived from a compoundselected from the group consisting of polyethylene oxide (PEO),polytetramethylene oxide (PTMO), and combinations thereof.

In some aspects, the polyamide polymeric network is physicallycrosslinked through, e.g., nonpolar or polar interactions between thepolyamide groups on the polymers, and is a thermoplastic polyamide, orin particular, a hydrophilic thermoplastic polyamide. In these aspects,component R₆ in Formula 13 and components R₇ and R₈ in Formula 15 formthe portion of the polymer often referred to as the “hard segment”, andcomponent R₂ forms the portion of the polymer often referred to as the“soft segment”. Therefore, in some aspects, the hydrogel can include aphysically crosslinked polymeric network having one or more polymerchains with amide linkages.

In some aspects, the polymeric network includes plurality of blockcopolymer chains, wherein at least a portion of the block copolymerchains each include a polyamide block and a hydrophilic block, (e.g., apolyether block) covalently bonded to the polyamide block to result in athermoplastic polyamide block copolymer polymeric network (i.e., apolyamide-polyether block copolymer). In these aspects, the polyamidesegments can interact with each other to form the crystalline region.Therefore, the polyamide block copolymer chains can each comprise aplurality of polyamide segments forming crystalline regions with otherpolyamide segments of the polyamide block copolymer chains, and aplurality of hydrophilic segments covalently bonded to the polyamidesegments.

In some aspects, the polyamide is polyamide-11 or polyamide-12 and thepolyether is selected from the group consisting of polyethylene oxide,polypropylene oxide, and polytetramethylene oxide. Commerciallyavailable thermoplastic polyamide hydrogels suitable for the present useinclude those under the tradename “PEBAX” (e.g., “PEBAX MH1657” and“PEBAX MV1074”) from Arkema, Inc., Clear Lake, Tex.), and “SERENE”coating (Sumedics, Eden Prairie, Minn.).

In various aspects, the polyamide polymeric network is covalentlycrosslinked, as previously described herein.

In some aspects, the polymeric network comprises or consists essentiallyof a polyolefin polymeric network. The polyolefin polymeric network canbe formed through free radical, cationic, and/or anionic polymerizationby methods well known to those skilled in the art (e.g., using aperoxide initiator, heat, and/or light).

In some aspects, the polymeric network can include one or more, or aplurality, of polyolefin chains. For instance, the polyolefin caninclude polyacrylamide, polyacrylate, polyacrylic acid and derivativesor salts thereof, polyacrylohalide, polyacrylonitrile, polyallylalcohol, polyallyl ether, polyallyl ester, polyallyl carbonate,polyallyl carbamate, polyallyl sulfone, polyallyl sulfonic acid,polyallyl amine, polyallyl cyanide, polyvinyl ester, polyvinylthioester, polyvinyl pyrrolidone, polyα-olefin, polystyrene, andcombinations thereof. Therefore, the polyolefin can be derived from amonomer selected from the group consisting of acrylamide, acrylate,acrylic acid and derivatives or salts thereof, acrylohalide,acrylonitrile, allyl alcohol, allyl ether, allyl ester, allyl carbonate,allyl carbamate, allyl sulfone, allyl sulfonic acid, allyl amine, allylcyanide, vinyl ester, vinyl thioester, vinyl pyrrolidone, α-olefin,styrene, and combinations thereof.

In some aspects, the polyolefin is derived from an acrylamide. Suitableacrylamides can include, but are not limited to, acrylamide,methacrylamide, ethylacrylamide, N,N-dimethylacrylamide,N-isopropylacrylamide, N-tert-butylacrylamide,N-isopropylmethacrylamide, N-phenylacrylamide,N-diphenylmethylacrylamide, N-(triphenylmethyl)methacrylamide,N-hydroxyethyl acrylamide, 3-acryloylamino-1-propanol,N-acryloylamido-ethoxyethanol, N-[tris(hydroxymethyl)methyl]acrylamide,N-(3-methoxypropyl)acrylamide,N-[3-(dimethylamino)propyl]methacrylamide,(3-acrylamidopropyl)trimethylammonium chloride, diacetone acrylamide,2-acrylamido-2-methyl-1-propanesulfonic acid, salts of2-acrylamido-2-methyl-1-propanesulfonic acid, 4-acryloylmorpholine, andcombinations thereof. For example, the acrylamide prepolymer can beacrylamide or methacrylamide.

In some cases, the polyolefin is derived from an acrylate (e.g.,acrylate and/or alkylacrylate). Suitable acrylates include, but are notlimited to, methyl acrylate, ethyl acrylate, propyl acrylate, isopropylacrylate, n-butyl acrylate, isobutyl acrylate, tert-butyl acrylate,hexyl acrylate, isooctyl acrylate, isodecyl acrylate, octadecylacrylate, lauryl acrylate, 2-ethylhexyl acrylate, 4-tert-butylcyclohexylacrylate, 3,5,5-trimethylhexyl acrylate, isobornyl acrylate, vinylmethacrylate, allyl methacrylate, methyl methacrylate, ethylmethacrylate, butyl methacrylate, isobutyl methacrylate, tert-butylmethacrylate, hexyl methacrylate, 2-ethylhexyl methacrylate, isodecylmethacrylate, lauryl methacrylate, stearyl methacrylate, cyclohexylmethacrylate, 3,3,5-trimethylcyclohexyl methacrylate, combinationsthereof, and the like. For example, acrylate prepolymer can be methylacrylate, ethyl methacrylate, or 2-hydroxyethyl methacrylate.

In some cases, the polyolefin is derived from an acrylic acid or aderivative or salt thereof. Suitable acrylic acids, but are not limitedto acrylic acid, sodium acrylate, methacrylic acid, sodium methacrylate,2-ethylacrylic acid, 2-propylacrylic acid, 2-bromoacrylic acid,2-(bromomethyl)acrylic acid, 2-(trifluoromethyl)acrylic acid, acryloylchloride, methacryloyl chloride, and 2-ethylacryloyl chloride.

In various aspects, the polyolefin can be derived from an allyl alcohol,allyl ether, allyl ester, allyl carbonate, allyl carbamate, allylsulfone, allyl sulfonic acid, allyl amine, allyl cyanide, or acombination thereof. For example, the polyolefin segment can be derivedfrom allyloxyethanol, 3-allyloxy-1,2-propanediol, allyl butyl ether,allyl benzyl ether, allyl ethyl ether, allyl phenyl ether, allyl2,4,6-tribromophenyl ether, 2-allyloxybenzaldehyde,2-allyloxy-2-hydroxybenzophenone, allyl acetate, allyl acetoacetate,allyl chloroacetate, allylcyanoacetate, allyl2-bromo-2-methylpropionate, allyl butyrate, allyltrifluoroacetae, allylmethyl carbonate, tert-butyl N-allylcarbamate, allyl methyl sulfone,3-allyloxy-2-hydroxy-1-propanesulfonic acid,3-allyloxy-2-hydroxy-1-propanesulfonic acid sodium salt, allylamine, anallylamine salt, and allyl cyanide.

In some cases, the polyolefin can be derived from a vinyl ester, vinylthioester, vinyl pyrrolidone (e.g., N-vinyl pyrrolidone), andcombinations thereof. For example, the vinyl monomer can be vinylchloroformate, vinyl acetate, vinyl decanoate, vinyl neodecanoate, vinylneononanoate, vinylpivalate, vinyl propionate, vinyl stearate, vinylvalerate, vinyl trifluoroacetate, vinyl benzoate, vinyl4-tert-butylbenzoate, vinyl cinnamate, butyl vinyl ether, tert-butylvinyl ether, cyclohexyl vinyl ether, dodecyl vinyl ether, ethyleneglycol vinyl ether, 2-ethylhexyl vinyl ether, ethyl vinyl ether,ethyl-1-propenyl ether, isobutyl vinyl ether, propyl vinyl ether,2-chloroethyl vinyl ether, 1,4-butanediol vinyl ether,1,4-cyclohexanedimethanol vinyl ether, di(ethylene glycol) vinyl ether,diethyl vinyl orthoformate, vinyl sulfide, vinyl halide, and vinylchloride.

In some aspects, the polyolefin can be derived from an alpha-olefin,such as 1-octene, 1-nonene, 1-decene, 1-undecene, 1-dodecene,1-tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-pentadecene,1-heptadecene, and 1-octadecene.

In various cases, the polyolefin segment containing R₇ can be derivedfrom a styrene. Suitable styrene monomers include styrene,α-bromostyrene, 2,4-diphenyl-4-methyl-1-pentene, α-methylstyrene,4-acetoxystyrene, 4-benzhydrylstyrene, 4-tert-butylstyrene,2,4-dimethylstyrene, 2,5-dimethylstyrene, 2-methylstyrene,3-methylstyrene, 4-methylstyrene, 2-(trifluoromethyl)styrene,3-(trifluoromethyl)styrene, 4-(trifluoromethyl)styrene,2,4,6-trimethylstyrene, vinylbenzyl chloride,4-benzyloxy-3-methoxystyrene, 4-tert-butoxystyrene,3,4-dimethoxystyrene, 4-ethoxystyrene, 4-vinylanisole, 2-bromostyrene,3-bromostyrene, 4-bromosytrene, 4-chloro-α-methylstyrene,2-chlorostyrene, 3-chlorostyrene, 4-chlorostyrene, 2,6-dichlorostyrene,2,6-difluorostyrene, 2-fluorostyrene, 3-fluorostyrene, 4-fluorostyrene,2,3,4,5,6-pentafluorostyrene, N,N-dimethylvinylbenzylamine,2-isopropenylaniline, 4-[N-(methylaminoethyl)aminomethyl]styrene,3-vinylaniline, 4-vinylaniline, (vinylbenzyl)trimethylammonium chloride,4-(diphenylphosphino)styrene, 3-isopropenyl-α,α-dimethylbenzylisocyanate, 3-nitrostyrene, 9-vinylanthracene, 2-vinylnaphthalene,4-vinylbenzocyclobutene, 4-vinylbiphenyl, and vinylbenzoic acid.

In some aspects, the polyolefin comprises a hydrophilic portion. Thehydrophilic portion of the polyolefin polymer chain can be pendant tothe polyolefin backbone, or the hydrophilic portion can function as acovalent crosslinker of the polyolefin polymer chain. In some aspects,the hydrophilic portion of the polyolefin polymer chain includes apendant polyether, polyester, polycarbonate, hydroxyl, lactone (e.g.,pyrrolidone), amino, carboxylate, sulfonate, phosphate, ammonium (e.g.,tertiary and quaternary ammonium), zwitterion group (e.g., a betaine,such as poly(carboxybetaine (pCB) and ammonium phosphonates such asphosphatidylcholine), or combinations thereof. Polyolefin polymer chainscontaining a pendant hydrophilic portion can be formed by copolymerizinga polyolefin monomer, as previously described, with a second polymerolefin monomer having a hydrophilic side chain, such as acrylic acid orpolyvinylpyrrolidone).

In some aspects, the polyolefin polymeric network includes a pluralityof polyolefin chains wherein at least a portion of the polyolefin chainseach comprise a first chain segment physically crosslinked to at leastone other polyolefin chain of the plurality of polyolefin chains and oneor more hydrophilic chain segments covalently bonded to the first chainsegment.

In other aspects, the hydrophilic portion of the polyolefin polymerchain is a hydrophilic crosslinker. The crosslinker can includepolyether, polyester, polycarbonate, hydroxyl, lactone (e.g.,pyrrolidone), amino, carboxylate, sulfonate, phosphate, ammonium (e.g.,tertiary and quaternary ammonium), a zwitterion (e.g., a betaine, suchas poly(carboxybetaine (pCB) and ammonium phosphonates such asphosphatidylcholine), and combinations thereof. The hydrophiliccrosslinker can be derived from a molecule having at least twoethylenically-unsaturated groups, such as a polyethylene glycoldimethacrylate.

Suitable commercially available polyolefin materials include, but arenot limited to the “POLYOX” product line by Dow Chemical, Midland Mich.,and styrenic block co-polymers. Examples of styrenic co-polymersinclude, but are not limited to TPE-s (e.g., styrene-butadiene-styrene(SBS) block copolymers, such as “SOFPRENE” andstyrene-ethylene-butylene-styrene (SEBS) block copolymer, such as“LAPRENE”, by SO.F.TER.

GROUP, Lebanon, Tenn.); thermoplastic copolyester elastomers (e.g.,thermoplastic elastomer vulconates (TPE-v or TPV)), such as “FORPRENE”by SO.F.TER. GROUP), “TERMOTON-V” by Termopol, Istanbul Turkey; and TPEblock copolymers, such as “SANTOPRENE” (ExxonMobil, Irving, Tex.).

In some aspects, the a monomer or prepolymer, such as the polyolefinprepolymer described above, is co-polymerized with a silicone prepolymerto form a silicone polymer chain of a silicone polymeric network. Inthese aspects, the silicone prepolymer, the polyolefin prepolymer, orboth can function as the crosslinker.

Examples of silicone monomers include, but are not limited to,3-methacryloxypropyl tris(trimethylsiloxy)silane (TRIS), andmonomethacryloxypropyl terminated polydimethylsiloxane (mPDMS), mvinyl[3-[3,3,3-trimethyl-1,1bis(trimethylsiloxy)-disiloxanyl]propyl]carbamate,3-methacryloxypropyl-bis(trimethylsiloxy)methyl silane, andmethacryloxypropylpentamethyl disiloxane.

In other aspects, the polymeric network comprises or consistsessentially of an ionomeric polymeric network including a plurality ofionomer chains. An ionomer is a copolymer formed of both neutrallycharged units and ionized units bonded to the polymer backbone, e.g., aspendant groups. Commonly the ionized units include carboxylic acidgroups. Synthesis of ionomers typically includes the step of firstintroducing the ionized units (e.g., acid groups) into the polymerchain, and then neutralizing a portion of the ionized units (e.g., witha metal cation). The ionomer can comprise units of acrylic acid,methacrylic acid, or both. The ionomer can comprise a copolymer ofethylene and methacrylic acid.

As previously discussed, the material of the present disclosure can be apolymeric hydrogel material.

The polymeric hydrogel can comprise or consist essentially of apolyurethane hydrogel. Polyurethane hydrogels are prepared from one ormore diisocyanate and one or more hydrophilic diol. The polymer may alsoinclude a hydrophobic diol in addition to the hydrophilic diol. Thepolymerization is normally carried out using roughly an equivalentamount of the diol and diisocyanate. Examples of hydrophilic diols arepolyethylene glycols or copolymers of ethylene glycol and propyleneglycol. The diisocyanate can be selected from a wide variety ofaliphatic or aromatic diisocyanates. The hydrophobicity of the resultingpolymer is determined by the amount and type of the hydrophilic diols,the type and amount of the hydrophobic diols, and the type and amount ofthe diisocyanates.

The polymeric hydrogel can comprise or consist essentially of a polyureahydrogel. Polyurea hydrogels are prepared from one or more diisocyanateand one or more hydrophilic diamine. The polymer may also include ahydrophobic diamine in addition to the hydrophilic diamines. Thepolymerization is normally carried out using roughly an equivalentamount of the diamine and diisocyanate. Typical hydrophilic diamines areamine-terminated polyethylene oxides and amine-terminated copolymers ofpolyethylene oxide/polypropylene. Examples are Jeffamine® diamines soldby Huntsman (The Woodlands, Tex., USA). The diisocyanate can be selectedfrom a wide variety of aliphatic or aromatic diisocyanates. Thehydrophobicity of the resulting polymer is determined by the amount andtype of the hydrophilic diamine, the type and amount of the hydrophobicamine, and the type and amount of the diisocyanate.

The polymeric hydrogel can comprise or consist essentially of apolyester hydrogel. Polyester hydrogels can be prepared fromdicarboxylic acids (or dicarboxylic acid derivatives) and diols wherepart or all of the diol is a hydrophilic diol. Examples of hydrophilicdiols are polyethylene glycols or copolymers of ethylene glycol andpropylene glycol. A second hydrophobic diol can also be used to controlthe polarity of the final polymer. One or more diacid can be used whichcan be either aromatic or aliphatic. Of particular interest are blockpolyesters prepared from hydrophilic diols and lactones of hydroxyacids.The lactone is polymerized on the each end of the hydrophilic diol toproduce a triblock polymer. In addition, these triblock segments can belinked together to produce a multiblock polymer by reaction with adicarboxylic acid.

The polymeric hydrogel can comprise or consist essentially of apolycarbonate hydrogel. Polycarbonates are typically prepared byreacting a diol with phosgene or a carbonate diester. A hydrophilicpolycarbonate is produced when part or all of the diol is a hydrophilicdiol. Examples of hydrophilic diols are hydroxyl terminated polyethersof ethylene glycol or polyethers of ethylene glycol with propyleneglycol. A second hydrophobic diol can also be included to control thepolarity of the final polymer.

The polymeric hydrogel can comprise or consist essentially of apolyetheramide hydrogel. Polyetheramides are prepared from dicarboxylicacids (or dicarboxylic acid derivatives) and polyether diamines (apolyether terminated on each end with an amino group). Hydrophilicamine-terminated polyethers produce hydrophilic polymers that will swellwith water. Hydrophobic diamines can be used in conjunction withhydrophilic diamines to control the hydrophilicity of the final polymer.In addition, the type dicarboxylic acid segment can be selected tocontrol the polarity of the polymer and the physical properties of thepolymer. Typical hydrophilic diamines are amine-terminated polyethyleneoxides and amine-terminated copolymers of polyethyleneoxide/polypropylene. Examples are Jeffamine® diamines sold by Huntsman(The Woodlands, Tex., USA).

The polymeric hydrogel can comprise or consist essentially of a hydrogelformed of addition polymers of ethylenically unsaturated monomers. Theaddition polymers of ethylenically unsaturated monomers can be randompolymers. Polymers prepared by free radical polymerization of one ofmore hydrophilic ethylenically unsaturated monomer and one or morehydrophobic ethylenically unsaturated monomers. Examples of hydrophilicmonomers are acrylic acid, methacrylic acid,2-acrylamido-2-methylpropane sulphonic acid, vinyl sulphonic acid,sodium p-styrene sulfonate,[3-(methacryloylamino)propyl]trimethylammonium chloride, 2-hydroxyethylmethacrylate, acrylamide, N,N-dimethylacrylamide, 2-vinylpyrrolidone,(meth)acrylate esters of polyethylene glycol, and (meth)acrylate estersof polyethylene glycol monomethyl ether. Examples of hydrophobicmonomers are (meth)acrylate esters of C1 to C4 alcohols, polystyrene,polystyrene methacrylate macromonomer and mono(meth)acrylate esters ofsiloxanes. The water uptake and physical characteristics are tuned byselection of the monomer and the amounts of each monomer type.

The addition polymers of ethylenically unsaturated monomers can be combpolymers. Comb polymers are produced when one of the monomers is amacromer (an oligomer with an ethylenically unsaturated group one end).In one case the main chain is hydrophilic while the side chains arehydrophobic. Alternatively the comb backbone can be hydrophobic whilethe side chains are hydrophilic. An example is a backbone of ahydrophobic monomer such as styrene with the methacrylate monoester ofpolyethylene glycol.

The addition polymers of ethylenically unsaturated monomers can be blockpolymers. Block polymers of ethylenically unsaturated monomers can beprepared by methods such as anionic polymerization or controlled freeradical polymerization. Hydrogels are produced when the polymer has bothhydrophilic blocks and hydrophobic blocks. The polymer can be a diblockpolymer (A-B) polymer, triblock polymer (A-B-A) or multiblock polymer.Triblock polymers with hydrophobic end blocks and a hydrophilic centerblock are most useful for this application. Block polymers can beprepared by other means as well. Partial hydrolysis of polyacrylonitrilepolymers produces multiblock polymers with hydrophilic domains(hydrolyzed) separated by hydrophobic domains (unhydrolyzed) such thatthe partially hydrolyzed polymer acts as a hydrogel. The hydrolysisconverts acrylonitrile units to hydrophilic acrylamide or acrylic acidunits in a multiblock pattern.

The polymeric hydrogel can comprise or consist essentially of a hydrogelformed of hybrid polymers. Hybrid polymers combine two or more types ofpolymers within each polymer chain to achieve the desired set ofproperties. Of particular interest are polyurethane/polyurea polymers,polyurethane/polyester polymers, polyester/polycarbonate polymers.

As previously discussed, it has also been found that particularhydrophilic polymers, including copolymers and/or polymer blends, can beeffective at reducing or preventing the accumulation of soil on theoutsole during wear on unpaved surfaces when the hydrophilic polymer isdisposed on at least a portion of the ground facing surface of anoutsole. In some examples, the hydrophilic polymer can be a film-formingpolymeric network. The hydrophilic polymers can have properties asdetermined using the test methods described herein, and are useful inachieving the specific performance benefits for the outsoles and/or anarticle of footwear as disclosed herein.

The hydrophilic polymers, including the polymer chains of the polymericnetwork of the material described herein, can be described based ontheir segmental polarity, as determined using the Polymer SegmentalPolarity Determination described below. The monomers polymerized to formthese polymers can be selected to produce polymers having particularsegmental polarities. For example, it has been found that polymershaving a segmental polarity of less than 1.0 as determined using thePolymer Segmental Polarity Determination described below have desirablelevels of water uptake. It has also been found that these polymershaving a segmental polarity of less than 1.0 can be effective inreducing soil adhesion.

The polymers of the polymeric network (including polymer blends) can beselected based on their individual segmental polarities, their molarproportion in the polymer network, and their molar volumes, in order toform a polymer network having an overall segmental polarity of less than1.0. For example, the polymeric network of the material can comprise aplurality of polymer chains formed from one or more relatively hard,hydrophobic or non-polar monomers and one or more relatively soft,hydrophilic or polar monomers such that the overall segmental polarityof the polymeric network is less than 1.0 as determined by the PolymerSegmental Polarity Determination described herein.

The polymer chains of the present disclosure can have a segmentalpolarity of less than 0.7, or less than 0.5, or less than 0.2. Thepolymer chains can have a segmental polarity of less than 0, or lessthan −0.2. The polymer chains can have a segmental polarity of less than0.2. At least 50% on a molar volume basis of the polymer chains presentin the polymeric network of the material can have a segmental polarityof less than 0.7, or less than 0.5, or less than 0.2, or less than 0, orless than −0.2. At least 80% on a molar volume basis of the polymerchains present in the polymeric network can have a segmental polarity ofless than 0.7, or less than or less than 0.5, or less than 0.2, or lessthan 0, or less than −0.2.

The polymer network can consist essentially of polymer chains having asegmental polarity of less than 0.7, or less than 0.5, or less than 0.2,or less than 0, or less than −0.2. Similarly, the polymeric blends andpolymeric networks of the present disclosurecan have an overallsegmental polarity of less than 0.7, or less than 0.5, or less than 0.2.The polymeric networks can have an overall segmental polarity of lessthan 0, or less than −0.2, or less than −1.0. The polymeric networks canhave an overall segmental polarity of less than 0.2.

As discussed above, the material can also optionally include one or moreadditives, such as antioxidants, colorants, stabilizers, anti-staticagents, wax packages, antiblocking agents, crystal nucleating agents,melt strength enhancers, anti-stain agents, stain blockers,hydrophilicity-enhancing additives, and combinations thereof.

Examples of particularly suitable additives includehydrophilicity-enhancing additives, such as one or more super-absorbentpolymers (e.g., superabsorbent polyacrylic acid or copolymers thereof).Examples of hydrophilicity-enhancing additives include thosecommercially available under the tradenames “CREASORB” or “CREABLOCK” byEvonik, Mobile, Ala., “HYSORB” by BASF, Wyandotte, Mich., “WASTE LOCKPAM” by M² Polymer Technologies, Inc., Dundee Township, Ill., and “AQUAKEEP” by Sumitomo Seika, New York, N.Y. The incorporation of thehydrophilicity-enhancing additive can assist the polymeric network byincreasing the water uptake rate and/or capacity for the material.Examples of suitable concentrations of the hydrophilicity-enhancingadditive in the material range from 0.1% to 15% by weight, from 0.5% to10% by weight, or from 1% to 5% by weight, based on the total weight ofthe material.

In some aspects, the outsole material or film can define an exterior orground-facing surface of the outsole. Alternatively, a water-permeablemembrane can define the exterior or ground-facing surface of theoutsole, and can be in direct contact with the outsole material or film.For example, at least a portion of the exterior surface of the outsolecan be defined by a first side of the water-permeable membrane, with theoutsole material or film present between the backing plate/outsolesubstrate and the membrane.

The level of water permeability of the water-permeable membrane ispreferably sufficient for water to rapidly partition from the exteriorsurface of the outsole (i.e., the first side of the membrane), acrossthe second side of the membrane, and into the material. For example, thelevel of water permeability of the water-permeable membrane can besufficient for a sample of the outsole obtained in accordance with theFootwear Sampling Procedure to have a water uptake capacity of greaterthan 40% by weight at 24 hours. The level of water permeability of thewater-permeable membrane can be sufficient for a sample of the outsoleobtained in accordance with the Footwear Sampling Procedure to have awater uptake capacity of greater than 40% by weight at 1 hour.

The articles of footwear of the present disclosure can be manufacturedusing a variety of different footwear manufacturing techniques. Forexample, the material (e.g., the material 116) and the optional backingplate or substrate can be formed using methods such as injectionmolding, cast molding, thermoforming, vacuum forming, extrusion, spraycoating, and the like.

In some aspects, the outsole is formed with the use of a co-extrudedoutsole plate. In this case, the material can be co-extruded with athermoplastic material used to form a thin backing substrate, where theresulting co-extruded material can be provided in a web or sheet form.The web or sheet can then be placed in a vacuum thermoforming tool toproduce the three-dimensional geometry of the outsole ground-facing side(referred to as an outsole face precursor). The backing substrateprovides a first function in this step by creating a structural supportfor the relatively thinner and weaker material. The outsole faceprecursor can then be trimmed to form its perimeter and orifices toreceive traction elements, thereby providing an outsole face.

The outsole face can then be placed in a mold cavity, where the materialis preferably positioned away from the injection sprues. Anotherthermoplastic material can then be back injected into the mold to bondto the backing substrate, opposite of the material. This illustrates thesecond function of the backing substrate, namely to protect the materialfrom the injection pressure. The injected thermoplastic material can bethe same or different from the material used to produce the backingsubstrate. Preferably, they can include the same or similar materials(e.g., both being thermoplastic polyurethanes). As such, the backingsubstrate and the injected material in the mold form the outsole backingplate, which is secured to the material (during the co-extrusion step).

In other aspects, the outsole is formed with the use of injectionmolding. In this case, a substrate material is preferably injected intoa mold to produce the outsole backing plate. The outsole backing platecan then be back injected with the material to produce the materialbonded to the outsole backing plate.

In either of the above aspects, after the outsole is manufactured, itcan be directly or indirectly secured to a footwear upper (i.e., theupper portion of an article of footwear which typically forms a voidinto which a wearer's foot can be inserted during wear) to provide thearticle of footwear of the present disclosure. In particular, thematerial can function as a ground-facing surface of the outsole, whichis positioned on the opposite side of the outsole backing plate from theupper.

Property Analysis and Characterization Procedure

Various properties can be determined for the outsoles of footwear inaccordance with the present disclosure according to the followingmethodologies. In some cases, the properties determined using these testmethods may be from samples of outsoles or of articles of footwear takenaccording to the Footwear Sampling Procedures. In other cases, theproperties determined using these test methods may be from samples ofmaterial taken according to the Co-extruded Film Sampling Procedure, theNeat Film Sampling Procedure, or the Neat Material Sampling Procedure.Regardless of whether the test was conducted on a sample taken from anoutsole or a sample of the material, the properties obtained by thesetests are understood to be representative of the outsoles of the presentdisclosure.

1. Sampling Procedures

As mentioned above, it has been found that when the material is securedto another substrate, the interfacial bond can restrict the extent thatthe material can take up water and/or swell. As such, various propertiesof the outsoles of the present disclosure can be characterized usingsamples prepared with the following sampling procedures:

A. Footwear Sampling Procedure

This procedure can be used to obtain a sample of an outsole of thepresent disclosure when the outsole comprising the material is acomponent of a footwear (i.e., an outsole not secured to an upper) or anarticle of footwear (e.g., where the material is bonded to an outsolesubstrate, such as an outsole backing plate). An outsole sampleincluding the material in a non-wet state (e.g., at 25° C. and 20%relative humidity) is cut from the article of footwear using a blade.This process is performed by separating the outsole from an associatedfootwear upper, and removing any materials from the outsole top surface(e.g., corresponding to the top surface 142) that can take up water andpotentially skew the water uptake measurements of the outsole. Forexample, the outsole top surface can be skinned, abraded, scraped, orotherwise cleaned to remove any upper adhesives, yarns, fibers, foams,and the like that could potentially take up water themselves.

The resulting sample includes the material and any outsole substratebonded to the material, and maintains the interfacial bond between thematerial and the associated outsole substrate. As such, this test cansimulate how the outsole (i.e., the portion of the outsole comprisingthe material such that the material defines a surface or side of theoutsole) will perform as part of an article of footwear. Additionally,this sample is also useful in cases where the interfacial bond betweenthe material and an optional outsole substrate is less defined, such aswhere the material of the material is highly diffused into the materialof the outsole substrate (e.g., with a concentration gradient).

The sample is taken at a location along the outsole that provides asubstantially constant material thickness for the material as present onthe outsole (within +/−10% of the average material thickness), such asin a forefoot region, midfoot region, or a heel region of the outsole,and has a surface area of 4 square centimeters (cm²). In cases where thematerial is not present on the outsole in any segment having a 4 cm²surface area and/or where the material thickness is not substantiallyconstant for a segment having a 4 cm² surface area, sample sizes withsmaller cross-sectional surface areas can be taken and the area-specificmeasurements are adjusted accordingly.

B. Co-Extruded Film Sampling Procedure

This procedure can be used to obtain a sample of material of the presentdisclosure when the material is co-extruded onto a backing substrate toform all or part of an outsole of the present disclosure. The backingsubstrate can be produced from a material that is compatible with thematerial of the material, such as a material used to form an outsolebacking plate for the material.

It has been found that samples taken from co-extruded films are suitablesubstitutes to samples taken from outsoles or articles of footwear.Additionally, this sample is also useful in cases where the interfacialbond between the material and a backing substrate is less defined, suchas where the material is highly diffused into the composition of thebacking substrate (e.g., with a concentration gradient).

In this case, the material is co-extruded with the backing substrate asa web or sheet having a substantially constant thickness for thematerial (within +/−10% of the average material thickness), and cooledto solidify the resulting web or sheet. A sample of the material securedto the backing substrate is then cut from the resulting web or sheet,with a sample size surface area of 4 cm², such that the material of theresulting sample remains secured to the backing substrate.

C. Neat Film Sampling Procedure

This procedure can be used to obtain a sample of material of the presentdisclosure when the material is isolated in a neat form (i.e., withoutany bonded substrate). In this case, the material is extruded as a webor sheet having a substantially constant material thickness for thematerial (within +/−10% of the average material thickness), and cooledto solidify the resulting web or sheet. A sample of the material havinga surface area of 4 cm² is then cut from the resulting web or sheet.

Alternatively, if a source of the material is not available in a neatform, the material can be cut from an outsole substrate of a footwearoutsole, or from a backing substrate of a co-extruded sheet or web,thereby isolating the material. In either case, a sample of the materialhaving a surface area of 4 cm² is then cut from the resulting isolatedmaterial.

D. Neat Material Sampling Procedure

This procedure can be used to obtain a sample of a material of thepresent disclosure. In this case, the material is provided in mediaform, such as flakes, granules, powders, pellets, and the like. If asource of the material is not available in a neat form, the material canbe cut, scraped, or ground from an outsole of a footwear outsole or froma backing substrate of a co-extruded sheet or web, thereby isolating thematerial.

2. Water Uptake Capacity Test

This test measures the water uptake capacity of a sample of the materialafter a given soaking duration. The sample can be a sample of an outsoleor article of footwear taken with the above-discussed Footwear SamplingProcedure, can be a sample of the material as present in a co-extrudedfilm taken using the Co-extruded Film Sampling Procedure, can be asample of the material as present in a neat film taken using the NeatFilm Sampling Procedure, or can be a sample of the material in neat formtaken using the Neat Material Sampling Procedure. The sample isinitially dried at 60° C. until there is no weight change forconsecutive measurement intervals of at least 30 minutes apart (e.g., a24-hour drying period at 60° C. is typically a suitable duration). Thetotal weight of the dried sample (Wt,_(sample,dry)) is then measured ingrams. The dried sample is then allowed to cool down to 25° C., and isfully immersed in a deionized water bath maintained at 25° C. After agiven soaking duration, the sample is removed from the deionized waterbath, blotted with a cloth to remove surface water, and the total weightof the soaked sample (Wt,_(sample,wet)) is measured in grams.

Any suitable soaking duration can be used. For many of the materials ofthe present disclosure, a 24-hour soaking duration is believed to besufficient for the material to achieve saturation (i.e., the materialwill be in its saturated state). As used herein, the expression “havinga water uptake capacity at 5 minutes of . . . ” refers to a soakingduration of 5 minutes, “having a water uptake capacity at 1 hour of . .. ” refers to a soaking duration of 1 hour, the expression “having awater uptake capacity at 24 hours of . . . ” refers to a soakingduration of 24 hours, and the like.

As can be appreciated, the total weight of a sample taken pursuant tothe Footwear Sampling Procedure or the Co-extruded Film SamplingProcedure includes the weight of the material as dried or soaked(Wt,_(material,dry) or Wt,_(material,wet)) and the weight of the outsoleor backing substrate (Wt,_(substrate)). In order to determine a changein weight of the material due to water uptake, the weight of thesubstrate (Wt,_(substrate)) needs to be subtracted from the samplemeasurements.

The weight of the substrate (Wt,_(substrate)) is calculated using thesample surface area (e.g., 4 cm²), an average measured thickness of thesubstrate in the sample, and the average density of the substratematerial. Alternatively, if the density of the material for thesubstrate is not known or obtainable, the weight of the substrate(Wt,_(substrate)) is determined by taking a second sample using the samesampling procedure as used for the primary sample, and having the samedimensions (surface area and material/substrate thicknesses) as theprimary sample. The material of the second sample is then cut apart fromthe substrate of the second sample with a blade to provide an isolatedsubstrate. The isolated substrate is then dried at 60° C. for 24 hours,which can be performed at the same time as the primary sample drying.The weight of the isolated substrate (Wt,_(substrate)) is then measuredin grams.

The resulting substrate weight (Wt,_(substrate)) is then subtracted fromthe weights of the dried and soaked primary sample (Wt,_(sample,dry) andWt,_(sample,wet)) to provide the weights of the material as dried andsoaked (Wt,_(material,dry) and Wt,_(material,wet)), as depicted below byEquations 1 and 2:Wt,_(material,wet)=Wt,_(sample,wet)−Wt,_(substrate)  (Equation 1)Wt,_(material,dry)=Wt,_(sample,dry)−Wt,_(substrate)  (Equation 2)

For samples taken pursuant to the Neat Film Sampling Procedure or theNeat Material Sampling Procedure, the substrate weight (Wt,_(substrate))is zero. As such, Equation 1 collapses toWt,_(material,dry)=Wt,_(sample,dry), and Equation 2 collapses toWt,_(material,wet)=Wt,_(sample,wet).

The weight of the dried material (Wt,_(material,dry)) is then subtractedfrom the weight of the soaked material (Wt_(,material,wet)) to providethe weight of water that was taken up by the material, which is thendivided by the weight of the dried material (Wt,_(,material,dry)) toprovide the water uptake capacity for the given soaking duration as apercentage, as depicted below by Equation 3:

$\begin{matrix}{{{Water}\mspace{14mu}{Uptake}\mspace{14mu}{Capacity}} = {\frac{{Wt},_{{film},{wet}}{- {Wt}},_{{film},{dry}}}{{Wt},_{{film},{dry}}}\left( {100\%} \right)}} & \left( {{Equation}\mspace{14mu} 3} \right)\end{matrix}$For example, “a water uptake capacity of 50% at 1 hour” means that thesoaked material in the sample weighed 1.5 times more than its dry-stateweight after soaking for 1 hour, where there is a 1:2 weight ratio ofwater to material. Similarly, “a water uptake capacity of 500% at 24hours” means that the soaked material in the sample weighed 5 times morethan its dry-state weight after soaking for 24 hours, where there is a4:1 weight ratio of water to material.3. Water Uptake Rate Test

This test measures the water uptake rate of a sample of an outsole or ofmaterial by modeling weight gain as a function of soaking time for asample with a one-dimensional diffusion model. The sample can be takenwith any of the above-discussed Footwear Sampling Procedure, Co-extrudedFilm Sampling Procedure, or the Neat Film Sampling Procedure. The sampleis initially dried at 60° C. until there is no weight change forconsecutive measurement intervals of at least 30 minutes apart (a24-hour drying period at 60° C. is typically a suitable duration). Thetotal weight of the dried sample (Wt,_(sample,dry)) is then measured ingrams. Additionally, the average thickness of the material for the driedsample is measured for use in calculating the water uptake rate, asexplained below.

The dried sample is then allowed to cool down to 25° C., and is fullyimmersed in a deionized water bath maintained at 25° C. Between soakingdurations of 1, 2, 4, 9, 16, and 25 minutes, the sample is removed fromthe deionized water bath, blotted with a cloth to remove surface water,and the total weight of the soaked sample (Wt,_(sample,wet,t)) ismeasured, where “t” refers to the particular soaking-duration data point(e.g., 1, 2, 4, 9, 16, or 25 minutes).

The exposed surface area of the soaked sample (A_(t)) is also measuredwith calipers for determining the specific weight gain, as explainedbelow. The exposed surface area refers to the surface area that comesinto contact with the deionized water when fully immersed in the bath.For samples obtained using the Footwear Sampling Procedure and theCo-extruded Film Sampling Procedure, the samples only have one majorsurface exposed. However, for samples obtained using the Neat FilmSampling Procedure, both major surfaces are exposed. For convenience,the surface areas of the peripheral edges of the sample are ignored dueto their relatively small dimensions.

The measured sample is fully immersed back in the deionized water bathbetween measurements. The 1, 2, 4, 9, 16, and 25 minute durations referto cumulative soaking durations while the sample is fully immersed inthe deionized water bath (i.e., after the first minute of soaking andfirst measurement, the sample is returned to the bath for one moreminute of soaking before measuring at the 2-minute mark).

As discussed above in the Water Uptake Capacity Test, the total weightof a sample taken pursuant to the Footwear Sampling Procedure or theCo-extruded Film Sampling Procedure includes the weight of the materialas dried or soaked (Wt,_(material,dry) or Wt,_(material,wet,t)) and theweight of the outsole or backing substrate (Wt,_(substrate)). In orderto determine a weight change of the material due to water uptake, theweight of the substrate (Wt,_(substrate)) needs to be subtracted fromthe sample weight measurements. This can be accomplished using the samesteps discussed above in the Water Uptake Capacity Test to provide theresulting material weights Wt,_(material,dry) and Wt,_(material,wet,t)for each soaking-duration measurement.

The specific weight gain (Ws,_(material,t)) from water uptake for eachsoaked sample is then calculated as the difference between the weight ofthe soaked sample (Wt,_(material,wet,t)) and the weight of the initialdried sample (Wt,_(material,dry)), where the resulting difference isthen divided by the exposed surface area of the soaked sample (A_(t)),as depicted below by Equation 4:

$\begin{matrix}{{Ws},_{{material},t}{= \frac{{Wt},_{{material},{wet},t}{- {Wt}},_{{material},{dry}}}{A_{t}}}} & \left( {{Equation}\mspace{14mu} 4} \right)\end{matrix}$where t refers to the particular soaking-duration data point (e.g., 1,2, 4, 9, 16, or 25 minutes), as mentioned above.

The water uptake rate for the material in the sample is then determinedas the slope of the specific weight gains (Ws,_(material,t)) versus thesquare root of time (in minutes), as determined by a least squareslinear regression of the data points. For the materials of the presentdisclosure, the plot of the specific weight gains (Ws,_(material,t))versus the square root of time (in minutes) provides an initial slopethat is substantially linear (to provide the water uptake rate by thelinear regression analysis). However, after a period of time dependingon the thickness of the material, the specific weight gains will slowdown, indicating a reduction in the water uptake rate, until thesaturated state is reached. This is believed to be due to the waterbeing sufficiently diffused throughout the material as the water uptakeapproaches saturation, and will vary depending on material thickness.

As such, for the material having an average dried material thickness (asmeasured above) less than 0.3 millimeters, only the specific weight gaindata points at 1, 2, 4, and 9 minutes are used in the linear regressionanalysis. In these cases, the data points at 16 and 25 minutes can beginto significantly diverge from the linear slope due to the water uptakeapproaching saturation, and are omitted from the linear regressionanalysis. In comparison, for the material having an average driedmaterial thickness (as measured above) of 0.3 millimeters or more, thespecific weight gain data points at 1, 2, 4, 9, 16, and 25 minutes areused in the linear regression analysis. The resulting slope defining thewater uptake rate for the sampled material has units of weight/(surfacearea-square root of time), such as grams/(meter²-minutes^(1/2)).

Furthermore, some material or substrate surfaces can create surfacephenomenon that quickly attract and retain water molecules (e.g., viasurface hydrogen bonding or capillary action) without actually drawingthe water molecules into the material or substrate. Thus, samples ofthese materials or substrates can show rapid specific weight gains forthe 1-minute sample, and possibly for the 2-minute sample. After that,however, further weight gain is negligible. As such, the linearregression analysis is only applied if the specific weight gain datapoints at 1, 2, and 4 minutes continue to show an increase in wateruptake. If not, the water uptake rate under this test methodology isconsidered to be about zero grams/(meter²-minutes^(1/2)).

4. Swelling Capacity Test

This test measures the swelling capacity of a sample of an outsole or ofmaterial in terms of increases in material thickness and material volumeafter a given soaking duration for a sample (e.g., taken with theabove-discussed Footwear Sampling Procedure, Co-extruded Film SamplingProcedure, or the Neat Material Sampling Procedure). The sample isinitially dried at 60° C. until there is no weight change forconsecutive measurement intervals of at least 30 minutes apart (a24-hour drying period is typically a suitable duration). The dimensionsof the dried sample are then measured (e.g., thickness, length, andwidth for a rectangular sample; thickness and diameter for a circularsample, etc. . . . ). The dried sample is then fully immersed in adeionized water bath maintained at 25° C. After a given soakingduration, the sample is removed from the deionized water bath, blottedwith a cloth to remove surface water, and the same dimensions for thesoaked sample are re-measured.

Any suitable soaking duration can be used. Accordingly, as used herein,the expressions “having a swelling thickness (or volume) increase at 5minutes of . . . ” refers to a soaking duration of 5 minutes, having aswelling thickness (or volume) increase at 1 hour of . . . ” refers to atest duration of 1 hour, the expression “having a swelling thickness (orvolume) increase at 24 hours of . . . ” refers to a test duration of 24hours, and the like.

The swelling of the material in the sample is determined by (i) anincrease in the material thickness between the dried and soakedmaterial, by (ii) an increase in the material volume between the driedand soaked material, or (iii) both. The increase in material thicknessbetween the dried and soaked material is calculated by subtracting themeasured material thickness of the initial dried material from themeasured material thickness of the soaked material. Similarly, theincrease in material volume between the dried and soaked material iscalculated by subtracting the measured material volume of the initialdried material from the measured material volume of the soaked material.The increases in the material thickness and volume can also berepresented as percentage increases relative to the dry-materialthickness or volume, respectively.

5. Contact Angle Test

This test measures the contact angle of a sample surface (e.g., of asurface of an outsole of the present disclosure where the surface isdefined by the material of the present disclosure, or a surface of aco-extruded film formed of the material, or a surface of a neat filmformed of the material) based on a static sessile drop contact anglemeasurement for a sample (e.g., taken with the above-discussed FootwearSampling Procedure, Co-extruded Film Sampling Procedure, or the NeatFilm Sampling Procedure). The contact angle refers to the angle at whicha liquid interface meets the solid surface of the sample, and is anindicator of how hydrophilic the surface is.

For a dry test (i.e., to determine a dry-state contact angle), thesample is initially equilibrated at 25° C. and 20% humidity for 24hours. For a wet test (i.e., to determine a wet-state contact angle),the sample is fully immersed in a deionized water bath maintained at 25°C. for 24 hours. After that, the sample is removed from the bath andblotted with a cloth to remove surface water, and clipped to a glassslide if needed to prevent curling.

The dry or wet sample is then placed on a moveable stage of a contactangle goniometer such as the goniometer commercially available under thetradename “RAME-HART F290” from Rame-Hart Instrument Co., Succasunna,N.J. A 10-microliter droplet of deionized water is then placed on thesample using a syringe and automated pump. An image is then immediatelytaken of the droplet (before material can take up the droplet), and thecontact angle of both edges of the water droplet are measured from theimage. The decrease in contact angle between the dried and wet samplesis calculated by subtracting the measured contact angle of the wetmaterial from the measured contact angle of the dry material.

6. Coefficient of Friction Test

This test measures the coefficient of friction of a sample surface(e.g., an outsole surface in accordance with the present disclosure, asurface of a co-extruded film formed of the material of the presentdisclosure, or a surface of a neat film formed of the material of thepresent disclosure) for a sample (e.g., taken with the above-discussedFootwear Sampling Procedure, Co-extruded Film Sampling Procedure, or theNeat Material Sampling Procedure). For a dry test (i.e., to determine adry-state coefficient of friction), the sample is initially equilibratedat 25° C. and 20% humidity for 24 hours. For a wet test (i.e., todetermine a wet-state coefficient of friction), the sample is fullyimmersed in a deionized water bath maintained at 25° C. for 24 hours.After that, the sample is removed from the bath and blotted with a clothto remove surface water.

The measurement is performed with an aluminum sled mounted on analuminum test track, which is used to perform a sliding friction test onthe sample by sliding it on the aluminum surface of the test track. Thetest track measures 127 millimeters wide by 610 millimeters long. Thealuminum sled measures 76.2 millimeters×76.2 millimeters, with a 9.5millimeter radius cut into the leading edge. The contact area of thealuminum sled with the track is 76.2 millimeters×66.6 millimeters, or5,100 square millimeters).

The dry or wet sample is attached to the bottom of the sled using a roomtemperature-curing two-part epoxy adhesive commercially available underthe tradename “LOCTITE 608” from Henkel, Düsseldorf, Germany. Theadhesive is used to maintain the planarity of the wet sample, which cancurl when saturated. A polystyrene foam having a thickness of about 25.4millimeters is attached to the top surface of the sled (opposite of thetest sample) for structural support.

The sliding friction test is conducted using a screw-driven load frame.A tow cable is attached to the sled with a mount supported in thepolystyrene foam structural support, and is wrapped around a pulley todrag the sled across the aluminum test track. The sliding or frictionalforce is measured using a load transducer with a capacity of 2,000Newtons. The normal force is controlled by placing weights on top of thealuminum sled, supported by the polystyrene foam structural support, fora total sled weight of 20.9 kilograms (205 Newtons). The crosshead ofthe test frame is increased at a rate of 5 millimeters/second, and thetotal test displacement is 250 millimeters. The coefficient of frictionis calculated based on the steady-state force parallel to the directionof movement required to pull the sled at constant velocity. Thecoefficient of friction itself is found by dividing the steady-statepull force by the applied normal force. Any transient value relatingstatic coefficient of friction at the start of the test is ignored.

7. Storage Modulus Test

This test measures the resistance of the a sample of material to beingdeformed (ratio of stress to strain) when a vibratory or oscillatingforce is applied to it, and is a good indicator of the material'scompliance in the dry and wet states. For this test, a sample isprovided in film form using the Neat Film Sampling Procedure, which ismodified such that the surface area of the test sample is rectangularwith dimensions of 5.35 millimeters wide and 10 millimeters long. Thematerial thickness can range from 0.1 millimeters to 2 millimeters, andthe specific range is not particularly limited as the end modulus resultis normalized according to material thickness.

The storage modulus (E′) with units of megaPascals (MPa) of the sampleis determined by dynamic mechanical analysis (DMA) using a DMA analyzercommercially available under the tradename “Q800 DMA ANALYZER” from TAInstruments, New Castle, Del., which is equipped with a relativehumidity accessory to maintain the sample at constant temperature andrelative humidity during the analysis.

Initially, the thickness of the test sample is measured using calipers(for use in the modulus calculations). The test sample is then clampedinto the DMA analyzer, which is operated at the following stress/strainconditions during the analysis: isothermal temperature of 25° C.,frequency of 1 Hertz, strain amplitude of 10 micrometers, preload of 1Newton, and force track of 125%. The DMA analysis is performed at aconstant 25° C. temperature according to the following time/relativehumidity (RH) profile: (i) 0% RH for 300 minutes (representing the drystate for storage modulus determination), (ii) 50% RH for 600 minutes,(iii) 90% RH for 600 minutes (representing the wet state for storagemodulus determination), and (iv) 0% RH for 600 minutes.

The E′ value (in MPa) is determined from the DMA curve according tostandard DMA techniques at the end of each time segment with a constantRH value. Namely, the E′ value at 0% RH (i.e., the dry-state storagemodulus) is the value at the end of step (i), the E′ value at 50% RH isthe value at the end of step (ii), and the E′ value at 90% RH (i.e., thewet-state storage modulus) is the value at the end of step (iii) in thespecified time/relative humidity profile.

The sample of the material can be characterized by its dry-state storagemodulus, its wet-state storage modulus, or the reduction in storagemodulus between the dry-state and wet-state materials, where wet-statestorage modulus is less than the dry-state storage modulus. Thisreduction in storage modulus can be listed as a difference between thedry-state storage modulus and the wet-state storage modulus, or as apercentage change relative to the dry-state storage modulus.

8. Glass Transition Temperature Test

This test measures the glass transition temperature (T_(g)) of a sampleof the material, where the material is provided in neat form, such aswith the Neat Film Sampling Procedure or the Neat Material SamplingProcedure, with a 10-milligram sample weight. The sample is measured inboth a dry state and a wet state (i.e., after exposure to a humidenvironment as described herein).

The glass transition temperature is determined with DMA using a DMAanalyzer commercially available under the tradename “Q2000 DMA ANALYZER”from TA Instruments, New Castle, Del., which is equipped with aluminumhermetic pans with pinhole lids, and the sample chamber is purged with50 milliliters/minute of nitrogen gas during analysis. Samples in thedry state are prepared by holding at 0% RH until constant weight (lessthan 0.01% weight change over 120 minute period). Samples in the wetstate are prepared by conditioning at a constant 25° C. according to thefollowing time/relative humidity (RH) profile: (i) 250 minutes at 0% RH,(ii) 250 minutes at 50% RH, and (iii) 1,440 minutes at 90% RH. Step(iii) of the conditioning program can be terminated early if sampleweight is measured during conditioning and is measured to besubstantially constant within 0.05% during an interval of 100 minutes.

After the sample is prepared in either the dry or wet state, it isanalyzed by DSC to provide a heat flow versus temperature curve. The DSCanalysis is performed with the following time/temperature profile: (i)equilibrate at −90° C. for 2 minutes, (ii) ramp at +10° C./minute to250° C., (iii) ramp at −50° C./minute to −90° C., and (iv) ramp at +10°C./minute to 250° C. The glass transition temperature value (in Celsius)is determined from the DSC curve according to standard DSC techniques.

9. Impact Energy Test

This test measures the ability of a sample of material (e.g., of anoutsole, of a co-extruded film, or of a neat film) to shed soil underparticular test conditions, where the sample is prepared using theCo-extruded Film Sampling Procedure or the Neat Film Sampling Procedure(to obtain a suitable sample surface area). Initially, the sample isfully immersed in a water bath maintained at 25° C. for 24 hours), andthen removed from the bath and blotted with a cloth to remove surfacewater.

The wet test sample is then adhered to an aluminum block model outsolehaving a 25.4-millimeter thickness and a 76.2 millimeters×76.2millimeters surface area, using a room temperature-curing two-part epoxyadhesive commercially available under the tradename “LOCTITE 608” fromHenkel, Düsseldorf, Germany. The adhesive is used to maintain theplanarity of the soaked sample, which can curl when saturated.

Four polyurethane cleats, which are commercially available under thetrade name “MARKWORT M12-EP” 0.5-inch (12.7 millimeter) tall cleats fromMarkwort Sporting Goods Company, St. Louis, Mo., are then screwed intothe bottom of the block in a square pattern with a 1.56-inch(39.6-millimeter) pitch. As a control reference, four identical cleatsare attached to an aluminum block model outsole without a sample ofmaterial attached.

To clog the model outsole cleats, a bed of wet soil of about 75millimeters in height is placed on top of a flat plastic plate. The soilis commercially available under the tradename “TIMBERLINE TOP SOIL”,model 50051562, from Timberline (subsidiary of Old Castle, Inc.,Atlanta, Ga.) and was sifted with a square mesh with a pore dimension of1.5 millimeter on each side. Water is then added to the dry soil toproduce wet soil with a moisture content of 20-22%. The model outsole isthen compressed into the wet soil under body weight and twisting motionuntil the cleats touch the plastic plate. The weight is removed from themodel outsole, and the model outsole is then twisted by 90 degrees inthe plane of the plate and then lifted vertically. If no wet soil clogsthe model outsole, no further testing is conducted.

However, if wet soil does clog the model outsole, the wet soil isknocked loose by dropping a 25.4-millimeter diameter steel ball weighing67 grams onto the top side of the model outsole (opposite of the testsample and clogged soil). The initial drop height is 152 millimeters (6inches) above the model outsole. If the wet soil does not come loose,the ball drop height is increased by an additional 152 millimeters (6inches) and dropped again. This procedure of increasing the ball dropheight by 152 millimeter (6 inch) increments is repeated until the wetsoil on the bottom of the outsole model is knocked loose.

This test is run 10 times per test sample. For each run, the ball dropheight can be converted into unclogging impact energy by multiplying theball drop height by the ball mass (67 grams) and the acceleration ofgravity (9.8 meters/second). The unclogging impact energy in Joulesequals the ball drop height in inches multiplied by 0.0167. Theprocedure is performed on both the model outsole with the materialsample and a control model outsole without the material, and therelative ball drop height, and therefore relative impact energy, isdetermined as the ball drop height for the model outsole with thematerial sample divided by the control model outsole without thematerial. A result of zero for the relative ball drop height (orrelative impact energy) indicates that no soil clogged to the modeloutsole initially when the model outsole was compressed into the testsoil (i.e., in which case the ball drop and control model outsoleportions of the test are omitted).

10. Soil Shedding Footwear Test

This test measures the soil shedding ability of an article of cleatedfootwear, and does not require any sampling procedure. Initially, theoutsole of the footwear (while still attached to the upper) is fullyimmersed in a water bath maintained at 25° C. for 20 minutes), and thenremoved from the bath and blotted with a cloth to remove surface water,and its initial weight is measured.

The footwear with the soaked outsole is then placed on a last (i.e.,foot form) and fixed to a test apparatus commercially available underthe tradename “INSTRON 8511” from Instron Corporation, Norwood, Mass.The footwear is then lowered so that the cleats are fully submerged inthe soil, and then raised and lowered into the soil at an amplitude of10 millimeters for ten repetitions at 1 Hertz. With the cleats submergedin the soil, the cleat is rotated 20 degrees in each direction ten timesat 1 Hertz. The soil is commercially available under the tradename“TIMBERLINE TOP SOIL”, model 50051562, from Timberline (subsidiary ofOld Castle, Inc., Atlanta, Ga.), and the moisture content is adjusted sothat the shear strength value is between 3 and 4 kilograms/cm² on ashear vane tester available from Test Mark Industries (East Palestine,Ohio.

After the test is complete, the footwear is carefully removed from thelast and its post-test weight is measured. The difference between thepost-test weight and the initial weight of the footwear, due to soilaccumulation, is then determined.

11. Polymer Segmental Polarity Determination

The polymer chains of the polymeric networks of the present disclosurecan be characterized based their segmental polarity. The segmentalpolarity of a polymer is a value which is calculated based on the levelof polarity of the various molecular fragments which form the polymer.The segmental polarities (SP) are calculated as follows:

$\begin{matrix}{{SP} = {1000 \times \frac{{\log_{10}\left( K_{{oil}\text{-}{water}} \right)} - 0.229}{MolVol}}} & \left( {{Equation}\mspace{14mu} 5} \right)\end{matrix}$

Here, log₁₀(K_(oil-water)) is the so-called log P value or PartitionCoefficient, and MolVol is the molecular volume for the compound beingstudied. For a compound M, K_(oil-water) is the ratio of the Mconcentrations in 1-octanol and in water:

$\begin{matrix}{{\log_{10}\left( K_{{oil}\text{-}{water}} \right)} = {\log_{10}\left( \frac{\lbrack M\rbrack_{octanol}}{\lbrack M\rbrack_{water}} \right)}} & \left( {{Equation}\mspace{14mu} 6} \right)\end{matrix}$

Log₁₀(K_(oil-water)) is calculated using the KOWWin program which isavailable from a United States Environmental Protection Agency website:http://www.epa.gov/opptintr/exposure/docs/episuite.htm. KOWWin is alsothe subject of a number of scientific papers, e.g. Benefenati et al.,“Predicting log P of Pesticides Using Different Software”, Chemosphere(2003), 53(9), 1155-64. KOWWin calculates log₁₀(K_(oil-water)) as a sumof contributions from molecular fragments:

$\begin{matrix}{{\log_{10}\left( K_{{oil}\text{-}{water}} \right)} = {0.229 + {\sum\limits_{{fragments}{\mspace{11mu}\;}{in}{\mspace{11mu}\;}{molecule}}{N_{frag}C_{frag}}}}} & \left( {{Equation}\mspace{14mu} 7} \right)\end{matrix}$

The molecular volume MolVol is calculated using the method described inZhao, Y. H. et al., J. Org. Chem. 2003, 68, 7368-7373. The physicalrationale for defining the segmental polarity in this way is thatFlory-Huggins theory and its derivatives show that the free energy ofmixing of molecules with very different sizes is better predicted byusing the volume fractions (aka segment concentrations) of each speciesrather than the mole fractions of each. For a recent discussion, seeFornasiero, F. et al., Macromolecules 2005, 38, 1364-1370.

The K_(oil-water) for the compound M is related to the free energies ofM-octanol and M-water mixing. But K_(oil-water) is expressed in terms ofmolar concentrations. The K_(oil-water) can be put onto a segmentalbasis by dividing by molecular volume, as is done in Equation 1.

Following are detailed segmental polarity (SP) calculations for twopolymers. The polymers were synthesized from:

A polyethylene glycol prepolymer, difunctional, Mn=˜1000 (PEG)

A polypropylene glycol prepolymer, trifunctional, Mn=˜4500 (PPO)

Butanediol (BDO)

Toluene di-isocyanate (TDI)

The weights of reactants used to prepare the two polymers are given inTable 1 below.

TABLE 1 Polymer PEG PPO BDO TDI #1 18.2 25 1.3 5 #2 18.2 25 1 5

Table 2 shows the moles of reactants for the two polymers, calculatedusing the molecular weights for each species:

TABLE 2 Polymer PEG PPO BDO TDI #1 0.0182 0.00558 0.01444 0.02874 #20.0182 0.00558 0.01111 0.02874

From the reactants and their levels, the different segments which makeup the two polymers are determined. The PEG prepolymer contains onaverage 22.7 —CH₂—CH₂—O— repeat units. The PPO prepolymer contains onaverage 77.6 —CH₂—CH(CH₃)—O— repeat units. The —OH moieties on the PEG,PPO, and BDO reacts with the —NCO moieties on the TDI to form urethanelinkages:—OH+—NCO→—NH—C(═O)O—

This means that the TDI-derived segment is best modelled as—O—C(═O)—NH—(C₆H₃(CH₃))—NH—C(═O)—O—. The BDO-derived segment is modelledas —CH₂—CH₂—CH₂—CH₂—. If the number of —OH groups and —NCO groups in thereactants were equal, the polymers could be modelled with these foursegments:

A: —CH₂—CH₂—O—

B: —CH₂—CH(CH₃)—O—

C: —CH₂—CH₂—CH₂—CH₂—

D: —O—C(═O)—NH—(C₆H₃(CH₃))—NH—C(═O)—O—

However, both polymers #1 and #2 contain excess OH. So a fifth segmentmust be included:

E: —OH

Table 3 shows the mole fractions of each type of segment in the twopolymers:

TABLE 3 Polymer A B C D E #1 0.45334 0.47241 0.01583 0.03149 0.02692 #20.45837 0.47765 0.01231 0.03184 0.01983

Once the segments are defined, log₁₀(K_(oil-water)) can be calculatedfor each segment. To do this, each segment is converted to a chemicallydiscrete molecule by capping all of the dangling bonds with methylgroups. So for the log₁₀(K_(oil-water)) calculation, the segments become

-   A′: CH₃—CH₂—CH₂—O—CH₃-   B′: CH₃—CH₂—CH(CH₃)—O—CH₃-   C′: CH₃—CH₂—CH₂—CH₂—CH₂—CH₃-   D′: CH₃—O—C(═O)—NH—(C₆H₃(CH₃))—NH—C(═O)—O—CH₃-   E′: CH₃—OH

To calculate log₁₀(K_(oil-water)) for the methyl-capped segment #1:

Start the KOWWin program.

Enter the SMILES notation for the segment: CCCOC. SMILES is anestablished notation for describing molecular structure. A descriptionwith guidelines to write a SMILES is available athttp://www.syrres.com/esc/docsmile.htm

Obtain the result log₁₀(K_(oil-water))=1.0492.

Finally, this raw log₁₀(K_(oil-water)) is converted back to the segmentlog₁₀(K_(oil-water)) value by subtracting the constant 0.229 and thecontributions from the two capping methyl groups:segment log₁₀(K _(oil-water))=raw log₁₀(K_(oil-water))−0.229−2×0.5473  (Equation 8)

For each segment, Table 4 shows the SMILES notation for themethyl-capped segment, the raw log₁₀(K_(oil-water)), and the segmentlog₁₀(K_(oil-water)).

TABLE 4 Raw log₁₀ Segment log₁₀ Segment SMILES (K_(oil-water))(K_(oil-water)) A CCCOC 1.0492 −0.2744 B CCC(C)OC 1.4668 0.1432 C CCCCCC3.2880 1.9644 D COC(═O)N(c1c(C)ccc(NC(═O)OC)c1) 1.5075 0.1839 E CO−0.6323 −1.4112

Next, molar volumes are computed for each of the segments. From Zhao etal., the formula for molar volume is:MolVol=20.58×N _(C)+7.24×N _(H)+14.71×N ₀+15.6×N _(N)−14.7×N_(ring)−5.92×(N _(atoms) +N _(dang)−2)  (Equation 9)

In equation 4, N_(C), N_(H), etc. are the number of C, H, etc. atoms inthe segment; N_(ring) is the number of rings in the segment; N_(atoms)is the total number of atoms in the segment, and N_(dang) is the numberof dangling bonds. Table 5 shows the volume for each segment:

TABLE 5 Segment N_(C) N_(H) N_(O) N_(N) N_(rings) N_(atoms) N_(dang)MolVol A 2 4 1 0 0 7 2 43.39 B 3 6 1 0 0 10 2 60.69 C 4 8 0 0 0 12 269.2 D 9 8 4 2 1 24 2 176.4 E 0 1 1 0 0 2 1 16.03

The segment mole fractions (Table 3), log₁₀(K_(oil-water)) values (Table4), and MolVol values (Table 5) are used to calculate SP values for thepolymers using equation 5:

$\begin{matrix}{{SP} = \frac{\Sigma_{t = {segments}}\left( {{MF}_{t} \times \left( {{Segment}\mspace{14mu}{\log_{10}\left( K_{{oil}\text{-}{water}} \right)}} \right)_{t}} \right)}{\Sigma_{t = {segments}}\left( {{MF}_{t} \times {MolVol}_{t}} \right)}} & \left( {{Equation}\mspace{14mu} 10} \right)\end{matrix}$

SP values for polymers #1 and #2 are shown in Table 6, along with thereactants weights.

TABLE 6 Polymer PEG PPO BDO TDI SP #1 18.2 25 1.3 5 −1.044 #2 18.2 25 15 −0.994

The segmental polarity of a polymeric blend or polymeric network isdetermined by first determining the segmental polarities of the polymerchains present in the blend or network. The overall segmental polarityof the blend or network is then determined by adding the segmentalpolarity contributed by each polymer chain based on the molar proportionof each of the polymer chains present in the blend or network and themolar volume of each of the polymer chains present in the blend ornetwork.

EXAMPLES

The present disclosure is more particularly described in the followingexamples that are intended as illustrations only, since numerousmodifications and variations within the scope of the present disclosurewill be apparent to those skilled in the art. Unless otherwise noted,all parts, percentages, and ratios reported in the following examplesare on a weight basis, and all reagents used in the examples wereobtained, or are available, from the chemical suppliers described below,or may be synthesized by conventional techniques.

1. Footwear Outsole Water Uptake Analysis

Test samples for Examples 1-5 were measured for water uptake capacitiesover multiple soaking durations. Each test sample was taken from aglobal football/soccer shoe outsole having an outsole of the presentdisclosure. Each outsole was initially manufactured by co-extruding thematerial with a backing substrate having a substrate thickness of 0.4millimeters, where the backing substrate material was an aromaticthermoplastic polyurethane commercially available under the tradename“ESTANE 2103-87AE” from Lubrizol Corporation, Wickliffe, Ohio.

For Examples 1-3, the material was a thermoplastic polyurethane hydrogelcommercially available under the tradename “TECOPHILIC TG-500” from theLubrizol Corporation, Wickliffe, Ohio, which included copolymer chainshaving aliphatic hard segments and hydrophilic soft segments (withpolyether chains). For Examples 4 and 5, the material was alower-water-uptake thermoplastic polyurethane hydrogel commerciallyavailable under the tradename “TECOPHILIC HP-60D-60” from the LubrizolCorporation, Wickliffe, Ohio.

For each example, the resulting co-extruded web was then sheeted, vacuumthermoformed, and trimmed to dimensions for an outsole face. The outsoleface was then back injected with another thermoplastic polyurethanecommercially available under the tradename “DESMOPAN DP 8795 A” fromBayer MaterialScience AG, Leverkusen, Germany to produce the outsolehaving the material defining the ground-facing surface, and the extrudedbacking substrate and back-injected material collectively forming theoutsole backing plate. Footwear uppers were then adhered to the topsides of the produced outsoles to provide the article of footwear.

Test samples for each example were then taken as described above in theFootwear Sampling Procedure, with the exception of the sample sizesdescribed below. In particular, annular test samples including thematerial and the outsole backing plate were cut out of the footwear.This was performed by initially cutting off the upper from the outsolenear the biteline where the outsole and upper meet.

A small guide hole in the center of the sample was then created(creating an inner diameter for the sample) to assist in cutting theannular sample with the desired outer diameter. All removable layersremaining on the top side of the outsole backing plate after cuttingwere peeled away from the test samples, including the sockliner,strobel, and insole board, while some residual adhesive remained on thesample. Each sample was taken from a central location in its respectiveregion (i.e., near a longitudinal midline) and generally in-between thecleats.

Test samples for Examples 1-3 were respectively taken from the forefootregion, the midfoot region, and the heel region of the outsole. Testsamples for Examples 4 and 5 were respectively taken from the forefootregion and the midfoot region. Each sample was taken from a centrallocation in its respective region (i.e., near a longitudinal midline)and generally in-between the cleats.

For comparison purposes, outsole samples were also taken from a globalfootball/soccer footwear having a thermoplastic polyurethanecommercially available under the tradename “DESMOPAN DP 8795 A” fromBayer MaterialScience AG, Leverkusen, Germany; where the outsoles didnot include an material of the present disclosure. For ComparativeExample A, an annular test sample was taken from the forefoot region ofthe outsole using the same technique as discussed above for Examples1-5. For Comparative Example B, a rectangular test sample was taken fromthe midfoot region of the outsole. Each sample was taken from a centrallocation in its respective region (i.e., near a longitudinal midline)and generally in-between the cleats.

The material thickness, outsole thickness, surface area, and materialvolume of each test sample was then measured and calculated. The wateruptake capacity for each test sample was then measured for differentsoaking durations, pursuant to the Water Uptake Capacity Test. Aftereach soaking duration, the total sample weight was recorded, and thewater uptake weight for each soaking duration was calculated bysubtracting out the dry sample weight from the given recorded totalsample weight.

The material weight was also calculated for each soaking duration bysubtracting out the weight of the sample outsole substrate, as describedin the Water Uptake Capacity Test. The outsole substrate weight wasdetermined by calculating its volume (from the outsole thickness andsurface area) and using the known density of the outsole backing platematerial. The water uptake capacity was then calculated for each soakingduration, as also described in the Water Uptake Capacity Test. Tables7A-7G shown below list the total sample weights, the water uptakeweights, the material weights, and the water uptake capacities for thetest samples of Examples 1-5 and Comparative Examples A and B overdifferent soaking durations.

TABLE 7A Total Sample Material Water Soak Time Weight Uptaken WaterWeight Uptake Sample (minutes) (grams) Weight (grams) (grams) CapacityExample 1 0 1.54 0.00 0.64 0% Example 1 2 1.72 0.18 0.77 28% Example 1 51.75 0.21 0.84 33% Example 1 10 1.84 0.30 0.90 47% Example 1 30 2.010.47 1.10 74% Example 1 60 2.18 0.64 1.22 101%

TABLE 7B Total Sample Material Water Soak Time Weight Uptaken WaterWeight Uptake Sample (minutes) (grams) Weight (grams) (grams) CapacityExample 2 0 1.50 0.00 0.51 0% Example 2 2 1.68 0.18 0.67 35% Example 2 51.75 0.25 0.73 49% Example 2 10 1.84 0.34 1.04 66% Example 2 30 2.150.65 1.33 127% Example 2 60 2.40 0.90 1.49 176%

TABLE 7C Total Sample Material Water Soak Time Weight Uptaken WaterWeight Uptake Sample (minutes) (grams) Weight (grams) (grams) CapacityExample 3 0 1.21 0.00 0.46 0% Example 3 2 1.36 0.15 0.51 32% Example 3 51.44 0.23 0.72 50% Example 3 10 1.52 0.31 0.88 67% Example 3 30 1.630.42 0.79 91% Example 3 60 1.80 0.59 1.12 127% Example 3 180 2.15 0.941.58 203% Example 3 300 2.30 1.09 1.72 235% Example 3 1260 2.57 1.361.93 294%

TABLE 7D Total Sample Material Water Soak Time Weight Uptaken WaterWeight Uptake Sample (minutes) (grams) Weight (grams) (grams) CapacityExample 4 0 1.06 0.00 0.18 0% Example 4 2 1.08 0.02 0.31 11% Example 4 51.11 0.05 0.35 28% Example 4 10 1.06 0.00 0.34 0% Example 4 30 1.11 0.050.28 28% Example 4 60 1.12 0.06 0.41 33% Example 4 180 1.14 0.08 0.3844% Example 4 300 1.10 0.04 0.38 22% Example 4 1260 1.10 0.04 0.36 22%

TABLE 7E Total Sample Material Water Soak Time Weight Uptaken WaterWeight Uptake Sample (minutes) (grams) Weight (grams) (grams) CapacityExample 5 0 1.14 0.00 0.21 0% Example 5 2 1.17 0.03 0.21 61% Example 5 51.07 −0.07 0.24 6% Example 5 10 1.19 0.05 0.26 72% Example 5 30 1.180.04 0.26 66% Example 5 60 1.19 0.05 0.27 72% Example 5 180 1.20 0.060.29 77% Example 5 300 1.19 0.05 0.36 72% Example 5 1260 1.20 0.06 0.2477%

TABLE 7F Soak Time Total Sample Uptaken Water Sample (minutes) Weight(grams) Weight (grams) Comparative Example A 0 1.26 0.00 ComparativeExample A 2 1.60 0.34 Comparative Example A 5 1.62 0.36 ComparativeExample A 10 1.56 0.30 Comparative Example A 30 1.62 0.36 ComparativeExample A 60 1.57 0.31

TABLE 7F Soak Time Total Sample Uptaken Water Sample (minutes) Weight(grams) Weight (grams) Comparative Example B 0 1.05 0.00 ComparativeExample B 2 1.05 0.00 Comparative Example B 5 1.05 0.00 ComparativeExample B 10 1.05 0.00 Comparative Example B 30 1.05 0.00 ComparativeExample B 60 1.05 0.00 Comparative Example B 180 1.06 0.01 ComparativeExample B 300 1.05 0.00 Comparative Example B 1260 1.06 0.01

As shown in Tables 7A-7C, there is significant change in the weight ofthe samples for Example 1-3, which was believed to be due to the highabsorbance of the material. The samples of Examples 4 and 5 were basedon a lower-absorbent material and used a thinner application whencompared to Examples 1-3. Both of these differences lead to lessresolution in the measurement, although the uptake percent (˜50% averagefor the two samples) is measurable. This illustrates how the wateruptake of an material is dependent on the water uptake properties of thematerial as well as the material thickness.

In comparison, the samples of Comparative Examples A and B demonstratedthe lack of water uptake for the comparator thermoplastics. Inparticular, the sample of Comparative Example A only showed a change inweight at the first time point, but no subsequent change. This isbelieved to be due to surface phenomenon of the sample (e.g., capillaryaction) rather than water uptake into the outsole. In particular, thebacking layer for Comparative Example A was rough (i.e., has microporesunrelated to the polymer chemistry) and fibers associated with shoeconstruction adhered to the backing layer that were not fully removedduring sample preparation. On the other hand, the sample of ComparativeExample B had a smooth outsole surface and all potential contaminantsare removed.

Examples 1-3 of a material comprising a hydrogel all had average wateruptake capacities at 1 hour of greater than 40% by weight. In fact, thematerial had average water uptake capacities at 1 hour of greater than80% by weight. Examples 4 and 5 of a different material comprising ahydrogel had average water uptake capacities at 180 minutes of greaterthan 40% by weight. In comparison, the comparative samples ofnon-hydrogel materials had average water uptake capacities at 24 hoursof less than 1% by weight.

In addition to the water uptake capacities, the test samples of Examples1-5 and Comparative Examples A and B were measured for thickness andvolumetric swelling, pursuant to the Swelling Capacity Test, over thesame soaking durations referred to above. Tables 8A-8G list the measuredsurface areas and material thicknesses, and the calculated materialvolumes for the test samples, and Tables 9A-9E list the materialthickness increase, the percentage material thickness increase, thematerial volume increase, the percentage material volume increase.

TABLE 8A Surface Sample Material Soak Time Area Thickness thicknessMaterial Sample (minutes) (mm²) (mm) (mm) volume (mm³) Example 1 0 3803.66 1.44 548 Example 1 2 379 3.75 1.75 664 Example 1 5 410 3.75 1.77726 Example 1 10 410 3.90 1.90 779 Example 1 30 451 4.18 2.11 951Example 1 60 481 4.34 2.18 1049

TABLE 8B Surface Sample Material Soak Time Area Thickness thicknessMaterial Sample (minutes) (mm²) (mm) (mm) volume (mm³) Example 2 0 4213.50 1.05 442 Example 2 2 415 3.70 1.40 582 Example 2 5 436 4.22 1.45633 Example 2 10 472 4.20 1.90 897 Example 2 30 561 4.15 2.05 1150Example 2 60 612 4.18 2.10 1285

TABLE 8C Surface Sample Material Soak Time Area Thickness thicknessMaterial Sample (minutes) (mm²) (mm) (mm) volume (mm³) Example 3 0 3472.95 1.15 399 Example 3 2 347 3.08 1.28 444 Example 3 5 369 3.46 1.68620 Example 3 10 399 3.58 1.89 755 Example 3 30 404 3.70 1.68 678Example 3 60 449 3.75 2.15 964 Example 3 180 513 4.00 2.65 1359 Example3 300 530 4.18 2.80 1485 Example 3 1260 581 4.35 2.87 1667

TABLE 8D Surface Sample Material Soak Time Area Thickness thicknessMaterial Sample (minutes) (mm²) (mm) (mm) volume (mm³) Example 4 0 3632.41 0.43 156 Example 4 2 366 2.56 0.73 267 Example 4 5 372 2.57 0.80298 Example 4 10 371 2.47 0.78 290 Example 4 30 374 2.47 0.65 243Example 4 60 379 2.55 0.93 352 Example 4 180 373 2.55 0.87 324 Example 4300 386 2.53 0.85 328 Example 4 1260 379 2.40 0.81 307

TABLE 8E Soak Surface Sample Material Material Time Area Thicknessthickness volume Sample (minutes) (mm²) (mm) (mm) (mm³) Example 5 0 3782.42 0.47 178 Example 5 2 377 2.50 0.48 181 Example 5 5 386 2.50 0.54208 Example 5 10 385 2.52 0.58 223 Example 5 30 384 2.53 0.59 227Example 5 60 388 2.50 0.59 229 Example 5 180 389 2.57 0.65 253 Example 5300 394 2.57 0.78 307 Example 5 1260 388 2.55 0.54 209

TABLE 8F Soak Surface Sample Time Area Thickness Sample (minutes) (mm²)(mm) Comparative Example A 0 405 2.90 Comparative Example A 2 417 2.90Comparative Example A 5 425 3.15 Comparative Example A 10 407 2.77Comparative Example A 30 416 2.77 Comparative Example A 60 426 2.87

TABLE 8G Soak Surface Sample Time Area Thickness Sample (minutes) (mm²)(mm) Comparative Example B 0 501 1.77 Comparative Example B 2 500 1.77Comparative Example B 5 502 1.77 Comparative Example B 10 503 1.75Comparative Example B 30 503 1.75 Comparative Example B 60 496 1.73Comparative Example B 180 499 1.73 Comparative Example B 300 503 1.74Comparative Example B 1260 501 1.73

TABLE 9A Material Percent Material Percent Soak thickness Materialvolume Material Time Increase thickness Increase volume Sample (minutes)(mm) Increase (mm) Increase Example 1 0 0  0% 0  0% Example 1 2 0.31 22%116 21% Example 1 5 0.33 23% 178 33% Example 1 10 0.46 32% 231 42%Example 1 30 0.67 47% 403 74% Example 1 60 0.74 51% 501 92%

TABLE 9B Material Percent Material Percent Soak thickness Materialvolume Material Time Increase thickness Increase volume Sample (minutes)(mm) Increase (mm) Increase Example 2 0 0  0% 0  0% Example 2 2 0.35 33%140  32% Example 2 5 0.40 38% 191  43% Example 2 10 0.85 81% 455 103%Example 2 30 1.00 95% 708 160% Example 2 60 1.05 100%  843 191%

TABLE 9C Material Percent Material Percent Soak thickness Materialvolume Material Time Increase thickness Increase volume Sample (minutes)(mm) Increase (mm) Increase Example 3 0 0  0% 0  0% Example 3 2 0.13 11%45 11% Example 3 5 0.53 46% 221 55% Example 3 10 0.74 64% 356 89%Example 3 30 0.53 46% 279 70% Example 3 60 1.00 87% 565 142%  Example 3180 1.50 130%  960 240%  Example 3 300 1.65 143%  1086 272%  Example 31260 1.72 150%  1268 318% 

TABLE 9D Material Percent Material Percent Soak thickness Materialvolume Material Time Increase thickness Increase volume Sample (minutes)(mm) Increase (mm) Increase Example 4 0 0  0% 0  0% Example 4 2 0.30 70%111 71% Example 4 5 0.37 86% 142 91% Example 4 10 0.35 81% 134 85%Example 4 30 0.22 51% 87 56% Example 4 60 0.50 116%  196 125%  Example 4180 0.44 102%  168 107%  Example 4 300 0.42 98% 172 110%  Example 4 12600.38 88% 151 96%

TABLE 9E Material Percent Material Percent Soak thickness Materialvolume Material Time Increase thickness Increase volume Sample (minutes)(mm) Increase (mm) Increase Example 5 0 0  0% 0  0% Example 5 2 0.01  2%3  2% Example 5 5 0.07 15% 30 17% Example 5 10 0.11 23% 45 26% Example 530 0.12 26% 49 28% Example 5 60 0.12 26% 51 29% Example 5 180 0.18 38%75 42% Example 5 300 0.31 66% 129 73% Example 5 1260 0.07 15% 31 18%

As can be seen in Tables 8A-8G and 9A-9E, the samples of Examples 1-5all show significant changes in both thickness and volume upon wateruptake. The thickness and volume change is even resolved for Examples 3and 4, where the water uptake test showed less change. The samples forComparative Examples A and B, however, did not show any change inthickness or volume. Even when Comparative Example A showed a change inweight, as discussed above, there was no corresponding thickness changebecause the uptaken water was not acting to swell the samples, as is thecase for Examples 1-5.

For Examples 1-5 of materials comprising a hydrogel, the materials hadan average swell thickness increase at 1 hour of greater than 20%. Infact, the material of Examples 1-3 had an average swell thicknessincrease at 1 hour of greater than 75%. In comparison, the comparatornon-hydrogel materials did not increase in thickness.

2. Material Water Uptake Capacity

Various samples of materials for Examples 6-18 were also tested todetermine their uptake capacities at 1 hour and 24 hours, pursuant tothe Water Uptake Capacity Test with either the Co-Extruded Film SamplingProcedure (co-extruded form) or the Neat Film Sampling Procedure (neatfilm form). For the co-extruded forms, the backing substrate was athermoplastic polyurethane commercially available under the tradename“DESMOPAN DP 8795 A” from Bayer MaterialScience AG, Leverkusen, Germany.

The material for Examples 6-8 was a thermoplastic polyurethane hydrogelcommercially available under the tradename “TECOPHILIC TG-500” from theLubrizol Corporation, Wickliffe, Ohio (same material as for Examples1-3). For Example 6, the material was in neat film form with a0.25-millimeter material thickness. For Example 7, the material was in aco-extruded form with a 0.13-millimeter material thickness. For Example8, the material was also in a co-extruded film form, but with a0.25-millimeter material thickness.

The material for Examples 9 and 10 was a lower-water-uptakethermoplastic polyurethane hydrogel commercially available under thetradename “TECOPHILIC HP-60D-60” from the Lubrizol Corporation,Wickliffe, Ohio (same as for Examples 4 and 5). For Example 9, thematerial was in a co-extruded film form with a 0.25-millimeter materialthickness. For Example 10, the material was in a neat film form with a0.13-millimeter material thickness.

The material material for Example 11 was a thermoplastic polyurethanehydrogel commercially available under the tradename “TECOPHILIC TG-2000”from the Lubrizol Corporation, Wickliffe, Ohio, where the material wasin a neat film form with a 0.13-millimeter material thickness. Thematerial of Example 12 was a thermoplastic polyurethane hydrogelcommercially available under the tradename “TECOPHILIC HP-93A-100” fromthe Lubrizol Corporation, Wickliffe, Ohio, where the material was in aco-extruded film form with a 0.13-millimeter material thickness.

The material materials for Examples 13-17 were also thermoplasticpolyurethane hydrogels derived from chain-extended TDI isocyanates andpolyether glycols, where the polyether glycol concentrations were variedto adjust the water uptake capacities. For these examples, the materialswere pressed into thick neat films having 3-millimeter materialthicknesses.

The material for Example 18 was a thermoplastic polyamide-polyetherblock copolymer hydrogel commercially available under the tradename“PEBAX MH1657” from Arkema, Inc., Clear Lake, Tex., where the materialwas in a neat film form with a 0.13-millimeter material thickness. Table10 lists the water uptake capacities for the samples of Examples 6-18.

TABLE 10 Water Uptake Capacity Water Uptake Capacity Sample (1 hour) (24hours) Example 6 341%  468% Example 7 260%  — Example 8 153%  168%Example 9 —  44% Example 10 29%  80% Example 11 415%  900% Example 1244% — Example 13 55% 238% Example 14 60% 250% Example 15 35% 184%Example 16 40% 167% Example 17 15%  69% Example 18 116%  100%

As shown, Examples 6-8 in Table 10 demonstrate the effects ofconstraining the material to a co-extruded backing substrate. Examples 9and 10 demonstrate the same effects with a lower uptake material.Example 11 is a neat film with relatively high water uptake, whileExample 12 is a coextruded form of a neat resin that has a water uptakecapacity in-between those of Examples 6 and 10. Examples 13-17 alsoexhibited good water uptakes, and included considerably thickermaterials (by about a factor of 10).

All of the materials of Examples 6-18 comprise a hydrogel. Examples 6,8, 9, 10, 11, 13, 14, 15, 16, 17 and 18 were all found to have wateruptake capacities of 40% or greater a 1 hour. Examples 6, 7, 8, 11, and18 were found to have water uptake capacities of greater than 100% at 1hour. Examples 6, 7, 8, 11, 13, 14, 16, and 18 were found to have wateruptake capacities of greater than 40% at 24 hours. Examples 6, 8, 11,13, 14, 15, 16, and 18 were found to have water uptake capacities of atleast 100% at 24 hours.

3. Material Water Uptake Rate and Swelling

Several samples (for Examples 1, 4, 6-8, and 10-12) were also tested todetermine their water uptake rates and swell capacities, pursuant to theWater Uptake Rate Test and the Swell Capacity Test. Table 5 lists thetest results for the samples of Examples 1, 4, 6-8, and 10-12.

TABLE 11 Water Uptake Rate Percent Material Percent Material (grams/thickness Increase volume Increase Sample m²-minutes^(1/2)) (1 hour) (1hour) Example 1 235 73% 130%  Example 4 58 72% 75% Example 6 752 89%117%  Example 7 173 318%  64% Example 8 567 177%  77% Example 10 33 43%88% Example 11 1270 69% 92% Example 12 172 153%  70%

As shown, the tested samples exhibited varying water uptake rates, wherethe samples having higher water uptake capacities (from Table 10) andthat were in neat form exhibited faster water uptake rates. Moreover,the swelling thickness and volume increases shown in Table 11 generallycorresponded to the water uptake capacities shown above in Table 10.

Examples 1, 4, 6, 7, 8, 10, 11 and 12 were found to have water uptakerates of greater than 20 grams/m²-minutes^(1/2)”. Examples 1, 6, 7, 8,11 and 12 were found to have water uptake rates of greater than 150grams/m²-minutes^(1/2)”. Examples 1, 4, 6, 7, 8, 10, 11 and 12 werefound to have swell thickness increases of greater than 20% at 1 hour.In fact, Examples 1, 4, 6, 7, 8, 10, 11 and 12 were found to have swellthickness increases of greater than 40% at 1 hour, and Examples 1, 4, 6,7, 8, 11 and 12 were found to have swell thickness increases of greaterthan 60% at 1 hour. Examples 1, 4, 6, 7, 8, 10, 11 and 12 were found tohave swell volume increases of at least 70%.

4. Material Contact Angle

The samples for Examples 6, 7, 10-12, and 18 were also tested todetermine their dry-state and wet-state contact angles, pursuant to theContact Angle Test. Table 12 below lists the corresponding dry and wetstatic sessile drop contact angles with their variations, as well as thedifference in contact angle between the dry and wet measurements.

TABLE 12 Average Dry Average Wet Material Dry Material Material WetMaterial Contact Angle Contact Angle Contact Angle Contact Angle ContactAngle Sample (degrees) (std dev) (degrees) (std dev) Difference Example6 87.6 2.6 66.9 4.9 20.7 Example 7 86.6 1.1 57.4 5.5 29.2 Example 1095.6 3.2 72.5 2.5 23.1 Example 11 79.5 2.4 64.7 2.3 14.8 Example 12 97.12.5 95.5 4.7 1.7 Example 18 66.2 5.0 52.0 3.7 14.2

The samples of Examples 6 and 7 show that there is no difference incontact angles between a neat film and the co-extruded film at therelevant thicknesses because contact angle is a surface property. Thesamples of Examples 10 and 11 show that a higher contact angle isgenerally present on a lower water uptake material (Example 10) comparedto a high water uptake material (Example 11) The sample of Example 18,based on polyamide copolymer chemistry, demonstrates that the basechemistry can affect the dry contact angle. However, in all cases, asubstantial reduction in contact angle is seen for wet materials whencompared to dry samples. As can be appreciated from the discussionherein, a low wet state contact angle, or a decrease in contact anglefrom dry state to wet state, or both, can be predictive of outsoles andmaterials which can effectively prevent or reduce accumulation of soil.

Examples 6, 7, 10, 11 and 18 had wet-state static sessile drop contactangles of less than 80 degrees. Examples 6, 7, 11 and 18 had wet-statestatic sessile drop contact angles of less than 70 degrees. Examples 6,7, 10, 11, and 18 had a drop in static sessile drop contact angle fromthe dry state to the wet state of at least 10 degrees. Examples 6, 7,10, and 11 had a drop in static sessile drop contact angle from the drystate to the wet state of at least 20 degrees.

5. Material Coefficient of Friction

The samples for Examples 7, 10-12, and 18-21 were also tested fordry-state and wet-state coefficients of friction, pursuant to theCoefficient Of Friction Test. The material for Example 19 was the samethermoplastic polyamide hydrogel as used for Example 18, where thematerial was in a co-extruded film form with a 0.13-millimeter materialthickness.

The material for Examples 20 and 21 was a thermoplasticpolyamide-polyether block copolymer hydrogel commercially availableunder the tradename “PEBAX MV1074” from Arkema, Inc., Clear Lake, Tex.For Example 20, the material was in a neat film form with a0.13-millimeter material thickness. For Example 21, the material was ina co-extruded film form with a 0.13-millimeter material thickness.

For comparison purposes, a film of a thermoplastic polyurethane(commercially available under the tradename “DESMOPAN DP 8795 A” fromBayer MaterialScience AG, Leverkusen, Germany; Comparative Example C),and a non-hydrogel thermoplastic polyamide (commercially available fromArkema, Inc., Clear Lake, Tex.; Comparative Example D) were also tested.Table 7 below lists the corresponding dry and wet coefficients offriction, as well as the percent reductions in the coefficients offriction between the dry and wet measurements.

TABLE 13 Coefficient Coefficient Percent Reduction of Friction ofFriction in Coefficient Sample (dry) (wet) of Friction Example 7 0.30.13 57% Example 10 0.63 0.11 83% Example 11 0.29 0.06 79% Example 121.22 0.54 56% Example 18 0.6 0.76 −27%  Example 19 0.65 0.31 52% Example20 0.59 0.47 20% Example 21 0.53 0.26 51% Comparative Example C 0.590.71 −20%  Comparative Example D 0.37 0.35  5%

A comparison the results between Examples 7, 10-12, and 19-21 toComparative Examples C and D in Table 13 illustrate how the water takeup by the materials of the present disclosure can reduce the coefficientof friction of the material surfaces. Example 18 exhibited an increasein coefficient of friction after soaking. This is believed to be due toa partial saturation state for the material, where the water present ator near the material surface is being drawn into the material, creatinga transitory tackier surface. As the material for Example 18 took upadditional water (data not shown), its coefficient of friction alsoreduced below its dry-state value.

Examples 7, 10, 11, 12, 19, 20, and 21 showed a difference between thedry-state coefficient of friction and the wet-state coefficient offriction (wet subtracted from dry) of at least 0.1, or of at least 20%.Examples 10, 11, 12, 19, and 21 had a difference of at least 0.2, or ofat least 50%.

6. Material Storage Modulus

The samples for Examples 6, 8-12, and 18 were also tested to determinetheir dry-state and wet-state storage modulus values, pursuant to theStorage Modulus Test. Table 14 lists the storage modulus values at 0%relative humidity (RH), 50% RH, and 90%, as well as the percentreductions between the 0% and 50% RH, and between the 0% and 90% RH.

TABLE 14 E′ (MPa) E′ (MPa) E′ (MPa) ΔE′50 ΔE′90 Sample 0% RH 50% RH 90%RH (%) (%) Example 6 766.6 548.3 0.03 29% 100%  Example 8 151.7 119 41.922% 72% Example 9 60.16 52.68 45.93 12% 24% Example 10 43.44 34.05 29.5822% 32% Example 11 514.9 396.8 0.86 23% 100%  Example 12 44.7 38.2 34.515% 23% Example 18 119.7 105.3 64.6 12% 46%

The mechanical properties of the sample materials and their changes uponwater uptake can demonstrate both soil shedding and durabilityproperties. First, storage modulus is inversely related to compliance,and a compliant surface is useful in preventing or reducing the adhesionof soil to the outsole, as discussed above. A decrease in the modulusupon exposure to moisture is representative of an increase in complianceof the material which has been found to be predictive of soil sheddingperformance of the material on an outsole. Additionally, the materialsof the present disclosure when dry are less compliant, which increasesdurability of the materials under dry conditions, while still allowingthe materials to increase in compliance when wet.

Examples 6, 8, 9, 10, 11, 12 and 18, when equilibrated at 50% RH, havewet-state storage moduli at least 10% below their dry state (0% RH)moduli. Additionally, Examples 6, 8, 9, 10, 11, 12 and 18, whenequilibrated at 90% RH, have wet-state storage moduli at least 20% belowtheir dry state (0% RH) moduli. Examples 6, 8, 11 and 18, whenequilibrated at 90% RH, have wet-state storage moduli at least 40% belowtheir dry state (0% RH) moduli.

7. Material Glass Transition Temperature

The samples for Examples 6, 8-12, and 18 were also tested to determinetheir dry-state and wet-state glass transition temperatures, pursuant tothe Glass Transition Temperature Test. Table 15 lists the dry and wetglass transition temperatures, as well as their reductions between thedry and wet states.

TABLE 15 Sample T_(g, dry) (° C.) T_(g, wet) (° C.) ΔT_(γ) (° C.)Example 6 −27.5 −70 −42.5 Example 8 −30 −63 −33 Example 9 −25 −31 −6Example 10 −20 −37.1 −17.1 Example 11 — −63 — Example 12 −49.59 −60.59−11 Example 18 −54.93 −64.76 −9.83

As can be seen in Table 15, when water is taken up into the materialscomprising a hydrogel (Examples 6, 8, 9, 10, 11, 12 and 18), itplasticizes the hydrogel. A larger drop in the glass transitiontemperature will typically be seen for a neat film (Examples 6 and 10)compared to a co-extruded version (Examples 8 and 9, respectively.)Interestingly, Example 11 showed no measurable glass transition whendry, which suggests that there is not enough amorphous material in thesample to create a measurable signal. The appearance of a glasstransition temperature after water uptake suggests that the material iseither significantly plasticized and/or the absorbent regions are highlycrystalline in the absence of water. The plasticization of thehydrogel-containing materials as evidenced by a drop in glass transitiontemperature from the dry-state to the wet-state can distinguish thehydrogel material from materials which take up water but are notplasticized by the water.

Examples 6, 8, 9, 10, 12 and 18 have wet-state glass transitiontemperatures at least 5 degrees below their dry-state glass transitiontemperatures. In fact, Examples 6, 8, and 10 have wet-state glasstransition temperatures at least 55 degrees below their dry-state glasstransition temperatures.

8. Impact Energy Test

The samples for Examples 7, 12, 14, 16, 17, 19, and 21 were also testedfor their abilities to shed soil, pursuant to the Impact Energy Test, asshown below in Table 16.

TABLE 16 Sample Relative Impact Energy Example 7 0.60 Example 12 0.90Example 14 0.00 Example 16 0.00 Example 17 0.83 Example 19 1.03 Example21 0.95

All of the samples listed in Table 16, with the exception of Example 19,show a reduction in the relative impact energy required to dislodgeadhered wet soil from the material when compared to the unmodifiedaluminum block. Example 19 showed a slight increase in adhesion energy.However, this is believed to be due to the thickness of the sample (3millimeters), which prevented the material from taking up sufficientwater during the soaking step.

Examples 7, 12, 14, 16, 17, and 21 required a relative impact energy ofless than 1.0 in order to dislodge adhered wet soil. Examples 7, 14, and16 required a relative impact energy of less than 0.65 in order todislodge adhered wet soil.

9. Soil Shedding from Footwear

Global football/soccer footwear for Examples 22 and 23 were also testedfor soil shedding abilities, pursuant to the Soil Shedding FootwearTest, where Example 22 included the same footwear and materials asdiscussed above for Examples 1-3, and where Example 23 included the samefootwear and materials as discussed above for Examples 4 and 5.

After the test, the sample for Example 22 had an average weight gain of28.3% as compared to a control without the material, and the sample forExample 23 had an avearage weight gain of 37.4% as compared to thecontrol. Both examples demonstrated that the use of the materials whenpre-soaked in water are effective in preventing or reducing wet soilaccumulation. Furthermore, the material with a higher water uptakecapacity, water uptake rate, and swelling capacity (Example 22) was moreeffective in reducing wet soil accumulation as compared to a materialhaving a lower water uptake capacity (Example 23).

10. Field Use

Global football/soccer footwear for Examples 24 and 25 were also testedon a closed course during game play, where Example 24 included the samefootwear and materials as discussed above for Examples 1-3 and 22, andwhere Example 25 included the same footwear and materials as discussedabove for Examples 4, 5, and 23. Five pairs of the footwear for Example24 were tested, one pair of the footwear for Example 25 was tested, andtwo pairs of control footwear were tested (which did not include anmaterial) (Comparative Examples E and F). The footwear, initially freeof soil, were then worn by players on the closed course while playingsoccer for 90 minutes during a rainy day.

The first 45 minutes were played on a natural grass field, and second 45minutes were played on an organic/sand/clay mix field. After the90-minute playing session, the shoes were investigated for theaccumulation of soil on the outsoles over the course of the game. Asseen from the images in FIGS. 20B-20F, the five pairs of shoes with thematerial of Example 24 accumulated little to no soil, while the twopairs of control footwear for Comparative Examples E and F accumulated asubstantial amount of soil. The pair of shoes with the material ofExample 25 also accumulated soil (as shown in FIG. 20A), but theaccumulated amount was somewhat less than the control footwear ofComparative Examples E and F (as shown in FIGS. 20G and 20H). Thisillustrates the effectiveness of the materials of the present disclosurein preventing or reducing the adherence of soil.

Additionally, the footwear for Examples 24 and 25 were also used forextended durations during games on the closed course to demonstrate thelimits of their durabilities. The materials for the footwear of bothExamples 24 and 25 continue to be effective in preventing or reducingthe accumulation of soil after 100 hours of game play without anysignificant abrasion or delamination. As such, the materials of thepresent disclosure are suitable for use as ground-facing surfaces forfootwear outsoles.

The present disclosure can be described in accordance with the followingnumbered clauses.

Clause 1. An outsole for an article of footwear, the outsole comprising:

a first surface of the outsole configured to be ground-facing; and asecond surface of the outsole opposing the first surface, the outsoleconfigured to be secured to an upper for an article of footwear; whereinthe outsole comprises a material defining at least a portion of thefirst surface, and the material compositionally comprises a polymericnetwork formed of a plurality of polymer chains.

Clause 3. The outsole of clause 1 or 2, wherein the polymeric networkcomprises a polymeric network formed of a plurality of copolymer chains.

Clause 2. The outsole of clause 1, wherein the polymeric networkcomprises a crosslinked polymeric network.

Clause 4. The outsole of any of clauses 1-3, wherein the polymer chainsof the polymeric network comprise polyurethane chain segments, polyamidechain segments, or both.

Clause 5. The outsole of any of clauses 1-4, wherein the polymer chainsof the polymeric network comprise polyurethane chain segments.

Clause 6. The outsole of any of clauses 1-5, wherein polymer chains ofthe polymeric network comprise polyamide chain segments.

Clause 7. The outsole of any of clauses 1-3, wherein the polymer chainsof the network consist essentially of polyurethane chain segments.

Clause 8. The outsole of any of clauses 1-3, wherein the polymer chainsof the network consist essentially of polyamide chain segments.

Clause 9. The outsole of any of clauses 1-8, wherein the plurality ofpolymer chains comprise

one or more hard segments physically crosslinked to other hard segmentsof the copolymer chains; and

one or more hydrophilic soft segments covalently bonded to the hardsegments.

Clause 10. The outsole of clause 9, wherein the one or more hardsegments comprise polyamide segments.

Clause 11. The outsole of clause 9 or 10, wherein the hard segments ofthe copolymer chains comprise carbamate linkages, amide linkages, orcombinations thereof.

Clause 12. The outsole of any of clauses 9-11, wherein the portions ofthe hydrophilic soft segments are covalently bonded to the hard segmentthrough carbamate linkages.

Clause 13. The outsole of any of clauses 9-12, wherein the hydrophilicsoft segments of the copolymer chains comprise polyether segments,polyester segments, polycarbonate segments, or combinations thereof.

Clause 14. The outsole of any of clauses 9-13, wherein at least aportion of the one or more hydrophilic soft segments constitute backbonesegments of the copolymer chain.

Clause 15. The outsole of any one of clauses 9-14, wherein at least aportion of the hydrophilic soft segments comprise one or more pendantpolyether groups.

Clause 16. The outsole of any of clauses 9-15, wherein the one or morehydrophilic soft segments are present in the copolymer chains at a ratioranging from 20:1 to 110:1 by weight relative to the one or more hardsegments.

Clause 17. The outsole of any of clauses 9-16, wherein the ratio of theone or more soft segments to the one or more hard segments ranges from40:1 by weight to 110:1.

Clause 18. The outsole of any of clauses 9-17, wherein the ratio of theone or more soft segments to the one or more hard segments ranges from60:1 by weight to 80:1.

Clause 19. The outsole of any of clauses 9-18, wherein the ratio of theone or more hydrophilic soft segments to the one or more hard segmentsrange from 40:1 to 80:1.

Clause 20. The outsole of any of clauses 9-19, wherein at least 50% on amolar volume basis of the polymer chains of the polymeric network have asegmental polarity of less than 1.0 as determined using the PolymerSegmental Polarity Determination.

Clause 21. The outsole of any of clauses 9-20, wherein the polymericnetwork consists essentially of polymer chains have a segmental polarityof less than 1.0 as determined using the Polymer Segmental PolarityDetermination.

Clause 22. The outsole of any of clauses 9-20, wherein at least 50% on amolar volume basis of the polymer chains of the polymeric network have asegmental polarity of less than 0.7 as determined using the PolymerSegmental Polarity Determination.

Clause 23. The outsole of any of clauses 9-20, wherein the polymericnetwork consists essentially of polymer chains have a segmental polarityof less than 0.7 as determined using the Polymer Segmental PolarityDetermination.

Clause 24. The outsole of any of clauses 9-20, wherein at least 50% on amolar volume basis of the polymer chains of the polymeric network have asegmental polarity of less than 0.2 as determined using the PolymerSegmental Polarity Determination.

Clause 25. The outsole of any of clauses 9-20, wherein the polymericnetwork consists essentially of polymer chains having a segmentalpolarity of less than 0.2 as determined using the Polymer SegmentalPolarity Determination.

Clause 26. The outsole of any of clauses 9-20, wherein at least 50% on amolar volume basis of the polymer chains of the polymeric network have asegmental polarity of less than 0 as determined using the PolymerSegmental Polarity Determination.

Clause 27. The outsole of any of clauses 9-20, wherein the polymericnetwork consists essentially of polymer chains having a segmentalpolarity of less than 0 as determined using the Polymer SegmentalPolarity Determination.

Clause 28. The outsole of any of clauses 9-20, wherein at least 50% on amolar volume basis of the polymer chains of the polymeric network have asegmental polarity of less than −0.2 as determined using the PolymerSegmental Polarity Determination.

Clause 29. The outsole of any of clauses 9-20, wherein the polymericnetwork consists essentially of polymer chains having a segmentalpolarity of less than −0.2 as determined using the Polymer SegmentalPolarity Determination.

Clause 30. The outsole of any of clauses 1-29, wherein the polymerchains are substantially free of aromatic groups.

Clause 31. The outsole of any of clauses 1-30, wherein the materialcomprises a thermoplastic polyurethane hydrogel.

Clause 32. The outsole of any of clauses 1-30, wherein the materialconsists essentially of a thermoplastic polyurethane hydrogel.

Clause 33. The outsole of clause 31 or 32, wherein the outsole furtherincludes an outsole substrate comprising a second thermoplasticpolyurethane, and the material is secured to the outsole substrate.

Clause 34. The outsole of any of clauses 1-31, wherein the materialcomprises a thermoplastic polyamide block copolymer hydrogel.

Clause 35. The outsole of any of clauses 1-30, wherein the materialconsists essentially of a thermoplastic polyamide block copolymerhydrogel.

Clause 36. The outsole of clause 34 or 35, wherein the outsole furtherincludes an outsole substrate comprising a second thermoplasticpolyamide, and the material is secured to the outsole substrate.

Clause 37. The outsole of any of clauses 1-36, wherein the material hasa water uptake capacity at 24 hours ranging from 100% by weight to 700%by weight, as characterized by the Water Uptake Capacity Test with theFootwear Sampling Procedure, the Co-Extruded Film Sampling Procedure,the Neat Film Sampling Procedure, or the Neat Material SamplingProcedure.

Clause 38. The outsole of any of clauses 1-37, wherein the materialexhibits a swell thickness increase at 1 hour greater than 50%, ascharacterized by the Swelling Capacity Test with the Footwear SamplingProcedure, the Co-Extruded Film Sampling Procedure, the Neat FilmSampling Procedure, or the Neat Material Sampling Procedure.

Clause 39. The outsole of any of clauses 1-38, wherein the materialexhibits a swell thickness increase at 1 hour greater than 150%, ascharacterized by the Swelling Capacity Test with the Footwear SamplingProcedure, the Co-Extruded Film Sampling Procedure, the Neat FilmSampling Procedure, or the Neat Material Sampling Procedure.

Clause 40. The outsole of clause 1-39, wherein the material has awet-state storage modulus when equilibrated at 90% relative humidity anda dry-state storage modulus when equilibrated at 0% relative humidity,each as characterized by the Storage Modulus Test with the Neat MaterialSampling Procedure, and wherein the wet-state storage modulus is lessthan the dry-state storage modulus of the material.

Clause 41. The outsole of clause 1-40, wherein the material in a drystate has a first material thickness ranging from 0.1 millimeters to 5millimeters.

Clause 42. The outsole of clause 1-41, wherein the material in a drystate has a first material thickness ranging from 0.1 millimeters to 1millimeter.

Clause 43. The outsole of clauses 1-42, wherein the material forms or ispresent on at least 80% of the first ground-facing surface of theoutsole.

Clause 44. The outsole of clause 1-43, wherein the first surface furthercomprises a plurality of traction elements.

Clause 45. An article of footwear comprising the outsole of clause 1-44and an upper for an article of footwear secured to the second surface ofthe outsole.

Clause 46. A method of manufacturing an article of footwear, the methodcomprising: providing an outsole according to clause 1-44; providing anupper; and securing the outsole and the upper to each other such thatthe material defines a ground-facing surface of the article of footwear.

Clause 47. The method of clause 46, wherein the providing the outsolecomprises securing the material to a first side of a backing substrateformed of a second material compositionally comprising a thermoplastic;thermoforming the material secured to the backing substrate to producean outsole face precursor, wherein the outsole face precursor includesthe material secured to the first side of the backing substrate; placingthe outsole face in a mold; and injecting a third materialcompositionally comprising a thermopolymer onto a second side of thebacking substrate of the outsole face while the outsole face is presentin the mold to produce an outsole, wherein the outsole comprises anoutsole substrate that includes the backing substrate and the thirdmaterial; and the material secured to the outsole substrate.

Clause 48. The method of clause 46 or 47, wherein the method furthercomprises trimming the outsole face precursor to produce an outsoleface, wherein the outsole face includes the material secured to thefirst side of the backing substrate before the placing the outsole facein the mold.

Clause 49. The method of any of clauses 46-48, wherein the material is athermoplastic material, and the securing the material to the first sideof the backing substrate comprises co-extruding the material and thesecond material to produce a web or sheet of the material secured to thebacking substrate.

Clause 50. A method of using an article of footwear, the methodcomprising: providing an article of footwear having an upper and anoutsole operably secured to the upper, wherein the outsole is an outsoleaccording to clause 1-44 and includes the material on a ground-facingside of the outsole; exposing the material to water to take up at leasta portion of the water into the material, forming wet material; pressingthe outsole with the wet material onto a ground surface to at leastpartially compress the wet material; and lifting the outsole from theground surface to release the compression from the wet material.

Clause 51. The method of using an article of footwear of clause 50,wherein the pressing expels a portion of the taken up water from the wetmaterial, for example, into soil of the ground surface.

Clause 52. The method of clause 50 or 51, further comprising the step oftaking up additional water into wet material after releasing thecompression from the material.

Clause 53. The method of any of clauses 50-52, wherein the materialswells when it takes up the water.

Clause 54. The method of any of clauses 50-53, wherein the steps ofpressing the outsole onto the surface and lifting the outsole from thesurface are performed in a foot strike motion.

Clause 55. The method of any of clauses 50-54, wherein the step ofexposing the material to the water is also performed in the foot strikemotion.

Clause 56. The method of any of clauses 50-55, wherein the exposing thematerial to water comprises soaking the outsole in the water.

Clause 57. The method of any of clauses 50-56, wherein the outsolefurther comprises a plurality of traction elements, and wherein themethod further comprises pressing at least a portion of the tractionelements into the ground surface prior to pressing the wet material ontothe ground surface.

Clause 58. Use of a material compositionally comprising a polymericnetwork formed of a plurality of polymer chains to prevent or reducesoil accumulation on a first surface of outsole, which first surfacecomprises the material, by providing the material on the first surfaceof the outsole, wherein the outsole optionally retains at least 10% lesssoil by weight as compared to a second outsole which is identical exceptthat the first surface of the second outsole is substantially free ofthe material.

Clause 59. The use of clause 58, wherein the outsole is an outsoleaccording to clause 1-44 and/or wherein the material is as furtherdefined in any one of clauses 2-40.

Clause 60. An outsole for an article of footwear, the outsolecomprising: a first side; and an opposing second side; wherein the firstside comprises a material compositionally comprising a polymericnetwork, wherein the material is a material according to clauses 2-40.

Although the present disclosure has been described with reference topreferred aspects, workers skilled in the art will recognize thatchanges may be made in form and detail without departing from the spiritand scope of the disclosure.

What is claimed is:
 1. An outsole for an article of footwear, theoutsole comprising: a first surface of the outsole configured to beground-facing; and a second surface of the outsole opposing the firstsurface, the second surface of the outsole configured to be secured toan upper for an article of footwear; wherein the outsole comprises amaterial defining at least a portion of the first surface, and thematerial comprises a crosslinked polymeric network, wherein thecrosslinked polymeric network comprises crystalline regions andamorphous hydrophilic regions, and wherein the crystalline regions arecovalently bonded to the amorphous hydrophilic regions, wherein theamorphous hydrophilic regions are present in the crosslinked polymericnetwork at a ratio of at least 20:1 by weigh relative to the crystallineregions, and wherein the outsole comprises one or more traction elementson the first surface.
 2. The outsole of claim 1, wherein the amorphoushydrophilic regions are covalently bonded to the crystalline regionsthrough carbamate linkages.
 3. The outsole of claim 1, wherein a ratioof the amorphous hydrophilic regions to the crystalline regions rangesfrom 20:1 to 110:1 by weight.
 4. The outsole of claim 1, wherein thecrosslinked polymeric network is a physically crosslinked polymernetwork.
 5. The outsole of claim 1, wherein the crosslinked polymericnetwork includes carbamate linkages.
 6. The outsole of claim 1, whereineach of the one or more traction elements comprises a terminal edge, andwherein the material is not present on the terminal edges of any of theone or more traction elements.
 7. The outsole of claim 1, wherein one ormore of the traction elements is selected from the group consisting of:a cleat, a stud, a spike, and a lug.
 8. The outsole of claim 1, whereinthe traction elements are integrally formed with the outsole.
 9. Theoutsole of claim 1, wherein the traction elements are removable tractionelements.
 10. An article of footwear comprising the outsole of claim 1and an upper for an article of footwear secured to the second surface ofthe outsole.
 11. The article of footwear of claim 10, wherein each ofthe one or more traction elements comprises a terminal edge, and whereinthe material is not present on the terminal edges of any of the one ormore traction elements.
 12. The article of footwear of claim 10, whereinone or more of the traction elements is selected from the groupconsisting of: a cleat, a stud, a spike, and a lug.
 13. The article offootwear of claim 10, wherein the traction elements are integrallyformed with the outsole.
 14. The article of footwear of claim 10,wherein the traction elements are removable traction elements.
 15. Amethod of manufacturing an article of footwear, the method comprising:providing an outsole according to claim 1, providing an upper; andsecuring the outsole and the upper to each other such that the materialdefines a ground-facing surface of the article of footwear.
 16. Themethod of claim 15, wherein the material is a thermoplastic material,wherein the outsole further comprises a backing substrate, and whereinthe material is secured to the backing substrate by co-extruding thematerial and the backing substrate.
 17. The method of claim 15, whereineach of the one or more traction elements comprises a terminal edge, andwherein the material is not present on the terminal edges of any of theone or more traction elements.
 18. The method of claim 15, wherein oneor more of the traction elements is selected from the group consistingof: a cleat, a stud, a spike, and a lug.
 19. The method of claim 15,wherein the traction elements are integrally formed with the outsole.20. The method of claim 15, wherein the traction elements are removabletraction elements.